Mountain Climbing

Minggu, 31 Oktober 2010

Mountain Climbing
I
INTRODUCTION
Mountain Climbing, ascending mountains, most commonly as a recreational activity. Mountain climbing is popular worldwide, wherever hills rise high enough to provide challenge. The activity’s rewards include the physical exertion it requires, the satisfaction of overcoming difficulties by working with others, the thrill of reaching a summit, and the unobstructed view from a mountaintop. Exploration and research are other reasons that people climb mountains.
Ascents can be either nontechnical (a hike up a path or a scramble over rocks, not requiring the safety of a rope), or technical (a climb up more difficult terrain that requires the use of rope and other specialized equipment). This article focuses on technical climbs, which involve all the elements of simple hikes but also require advanced knowledge and equipment. Making technical climbs is also known as mountaineering.
Since ancient times, people have viewed mountain peaks as towering objects of myth, spiritual inspiration, and romantic beauty. Early peoples made ascents only to hunt game, to rescue lost or strayed animals, or to gain a military advantage over an enemy. Eventually, the unknown and inaccessible ceased to be something to be feared and avoided, and the conquest of the major mountain peaks and ranges of the world began. Mountaineering as a sport was born on August 8, 1786, with the first ascent of Mont Blanc (4,810 m/15,782 ft), one of Europe’s tallest peaks. Since that ascent, mountain climbing has evolved into three related sports: alpine climbing, ice climbing, and rock climbing. These sports require the same fundamental techniques.
II
CLIMBING FUNDAMENTALS
Experienced climbers prepare for a climb by buying a topographical map and a regional guidebook with charts of the expected terrain and descriptions of the mountain’s approach trails. Climbers begin major ascents by hiking to the base of the mountain, where they set up an overnight camping spot, known as a base camp. Early the next morning, they begin their ascent. On climbs that last only one day, experienced climbers attempt to reach the summit by noon, before afternoon thunderstorms, lightning, hail, and rain increase the danger of the climb. Climbers also make sure they have enough daylight to rappel (slide in a controlled fashion down climbing ropes) back to the mountain’s base and reach base camp before dark. On rare occasions climbers are caught in the dark and must resort to headlamps or flashlights to find their way back to camp. On ascents that last more than one day, an early start gives climbers enough time to set up their next camp on the mountain before nightfall. If there is snow on the route, starting early means that the frozen surface will not melt before the climbers cross it.
Because mountain climbers surmount dangerous terrain by using ropes and other equipment, they almost always climb in teams. The basic team is composed of two people, the leader and the second. Each has one end of the climbing rope tied into his or her climbing harness, a device that secures the climber to the rope in case of a slip. The leader’s job is to lead the climb by following a natural line or path to each successive ledge or resting spot. The leader also places climbing equipment known as hardware in cracks, snow, and ice at various points along the ascent. When attached to the climbing rope, the hardware becomes a series of anchors that hold a climber in the event of a fall.
The second feeds out rope as the leader progresses upwards. Paying out the rope (or conversely, pulling it in) is called belaying. The second also passes the rope around his or her waist or through a friction device that attaches to the climbing harness. Should the leader fall, the second can hold tightly to the rope, which creates enough friction to stop the rope’s movement and break the leader’s fall.
After the leader reaches a ledge and secures several pieces of hardware for a belay anchor, the second begins climbing, following the leader’s route and gathering the hardware. When the second reaches the leader, the team rests and then proceeds by climbing another rope length, or pitch. Because leading is stressful and tiring, the leader and the second sometimes switch positions, a process called swinging leads.
III
ALPINE CLIMBING
The style of mountaineering under which these basic climbing techniques developed is called alpinism, or alpine climbing, and this style encompasses much of the equipment, technique, and safety precautions that form the basis for ice climbing and rock climbing. Alpine climbing began in the European Alps in the late 18th century and is now practiced in all mountain ranges of the world. The most popular alpine climbing areas in the United States are the Colorado Rocky Mountains, the Sierra Nevada range in California, the Cascade Range of the northwestern United States and southwestern Canada, and the Alaska Range in the vicinity of Mount McKinley (6,194 m/20,320 ft). Alpine climbing involves the continuous ascent of a mountain peak over a period of one to several days by a team of at least two alpinists. Teams may consist of as many as four climbers. The climbers carry all the equipment they need—a camping stove and fuel, sleeping bags, sleeping mats, a tent or bivouac sack, first aid gear, a water bottle, and food. Each night the climbers bivouac, or spend the night on a mountain ledge, before continuing upward.
A
Equipment
Alpine climbers try to stay warm and dry, so proper clothing is essential. They avoid using cotton clothing because once wet, it conducts heat away from the body. Instead, many mountaineers use synthetic underwear; fleece hats, jackets, and pants; and jackets and snow pants made of waterproof, breathable material such as Gore-Tex. These types of clothing allow sweat and water vapor to escape from the skin through the clothing. By keeping warm and dry, mountaineers avoid the dangers of severely chilling their body core, which can lead to hypothermia. For more information on hypothermia and other hazards associated with mountain climbing, see the Mountain Safety section of this article.
Preferred mountaineering footwear is either heavy-duty, stiff-soled boots made of leather or synthetic material, or lightweight plastic boots that are completely waterproof. Mountaineers wear fiberglass or high-strength plastic helmets to protect their heads from falling pieces of rock or ice, as well as from head injuries if they fall themselves.
Mountain climbers use many different tools. The most basic of these are climbing harnesses, climbing ropes, ice axes, and crampons. Climbers also use a variety of types of hardware to anchor themselves to the mountainside.
A climbing harness is an adjustable set of straps that buckle around the waist and thighs of a climber. Most harnesses also come with special, easy-to-reach loops for attaching hardware and other climbing tools. The harness serves as an anchor for one end of the climbing rope. In the event of a fall, the anchors set in the mountainside halt the fall, and the harness holds the climber tight but does not restrict movement or breathing.
Climbing ropes are specially made lines of a high-strength nylon called Perlon. Ropes that measure 50 m (164 ft) in length and 10.5 mm (2/5 in) in diameter are standard for rock climbing. Ropes 60 m (197 ft) in length and 9 mm (1/3 in) in diameter are preferred for alpine and ice climbing; these ropes are usually waterproof, or everdry, so that they will not freeze and become stiff in cold or wet conditions.
Ice axes have either a metal or fiberglass shaft. One end of the shaft is a pointed metal spike. The other end is topped with a head that has a metal pick with serrated teeth on one side, and a straight, flat, metal blade called an adze on the other. Ice axes have many uses. One of the most common is to help the climber stay balanced on steep slopes. The climber swings the axe with a short, quick movement to lodge the pick in snow or ice, creating a secure anchor. If a climber should slip and begin sliding down a snowfield, a self-arrest can be performed by turning face down on the snow and burying the pick in the snow surface. The climber’s weight over the pick and firm grip on the ice axe usually stop any downward movement. Mountaineers also use the axe to chop steps in snow or ice. Longer axes are used as walking sticks and for probing crevasses during glacier travel.
Alpine climbers gain a foothold on steep and snowy slopes by using crampons. Invented in 1908 by British climber Oscar Eckenstein, crampons are frameworks of sharp metal teeth that fasten to mountaineering boots and grip the snow and ice. They attach to the boots with straps that lace around the ankles or by snaps that connect to the boot sole. Basic mountaineering crampons are hinged between the sole and the heel, have straps, and have 10 or 12 points. More technical crampons have two teeth pointing forward. These teeth, called front points, allow a climber to kick straight into the ice or snow on especially steep slopes.
When attached to a climber’s rope, hardware provides anchors to steep slopes. Hardware can include such items as nuts and chocks, which are wedge-shaped or hexagonal pieces of aluminum alloy attached to a wire cable or a Perlon sling. Climbers can wedge these high-strength pieces of metal into cracks and fissures in the rock. Hardware also includes spring-loaded camming devices that wedge into cracks in the rock. These range in size from 1 to 15 cm (.5 to 6 in) wide. Other types of hardware include ice screws, which are threaded, aluminum alloy tubes with sharp teeth that are screwed directly into ice; and snow pickets, lightweight metal stakes that climbers hammer into the snow.
In the eye (or hole) at the end of each of these devices the climber clips in a carabiner, an oval-shaped, spring-loaded metal link. The link attaches to a short length of nylon webbing and another carabiner, through which the climbing rope attaches. Should the climber slip, this series of anchors, carabiners, and webbing acts as a shock absorber. It distributes the pressure of the fall to each of the climber’s anchors and reduces the risk of a long and dangerous drop.
All mountaineers also carry several other items: a compass; topographic maps that indicate elevations, place names, and geographical formations in the area; and an altimeter, which calculates altitude above sea level. Altimeters, which work on barometric principles, can also be used to anticipate weather changes.
B
Mountain Safety
An accident while mountain climbing generally has unexpected and negative consequences. A seemingly small mistake, such as twisting an ankle in loose rocks, can quickly turn into a dangerous situation if the climber is on difficult terrain and is still some distance from the base camp. Climbers can minimize the consequences of these mistakes by traveling in groups, carrying first aid equipment, and being cautious in their route planning. Alpine climbers are also exposed to perils beyond their control, such as hidden crevasses and avalanches, and because of the inhospitable environment of most mountains, they risk exposing themselves to hypothermia and altitude sickness. Experienced mountaineers plan ahead for all contingencies and let others know their destination and planned return time.
Crevasses are deep ice fissures or large cracks within a glacier. Many times crevasses are hidden under a covering of snow, making them difficult to identify. Their steep, slippery sides make them almost impossible to climb out of without assistance. For this reason, climbers often rope together and secure themselves to each other when traveling on glaciers and snowfields. Should one partner fall in a crevasse, the other can break the fall and then pull their partner out.
Avalanches are sudden flows of a large mass of snow or ice down a slope or cliff, sometimes at speeds exceeding 160 km/h (100 mph). They occur when heavy snowfall accumulates on steep slopes and the underlying snow pack cannot support the new snow’s weight. Mountaineers can minimize avalanche dangers by staying aware of rapid changes of weather, especially increases in temperature and wind. They should also avoid steep, narrow chutes that provide ideal channels for avalanches.
Hypothermia occurs when the body becomes too chilled to generate enough warmth for vital organs such as the heart and lungs. Most climbers understand that hypothermia is a danger during extremely cold weather, but it also can occur when temperatures are well above freezing. In fact, most cases occur when the outside temperature is from 7° to 10°C (45° to 50°F). Avoiding hypothermia requires several simple precautions. Mountain climbers should stay dry and avoid cotton clothing, which dries slowly and sucks away body warmth as it does dry. They should eat, drink water, and rest frequently, helping them maintain energy levels.
Altitude sickness, also known as mountain sickness, is caused by insufficient oxygen at high elevations. It causes dizziness, shortness of breath, and confusion, and it can strike climbers at any elevation above 2,400 m (about 8,000 ft). Mountaineers who ascend to higher altitudes often take a day or two to become accustomed to their new environment. They climb slowly when going above 4,500 m (15,000 ft). If climbers develop symptoms of altitude sickness, they should descend immediately to a lower altitude before the condition worsens. Some climbers use bottled oxygen to combat the effects of the sickness and aid their efforts at higher altitudes.
C
Conditioning and Learning to Climb
Mountaineers need to be in excellent physical shape, and many people train for mountain climbing by running, hiking, and bicycling. While climbing, mountaineers must remain relaxed and focused in tense situations, such as when they are having trouble picking the correct route up or down a mountain, when a storm is approaching, or when night is falling.
Traditionally, beginning mountaineers learned safe climbing skills through a mountain apprenticeship. Older, more experienced climbers and guides accompanied beginners on a number of ascents and acted as mentors, demonstrating techniques and providing encouragement. Today, beginners can follow the apprenticeship route or learn these skills from a qualified friend or from climbing schools or guide services that are certified by such organizations as the American Mountain Guides Association (AMGA).
IV
ICE CLIMBING
Ice climbing grew out of traditional mountaineering, and ice climbers use the basic equipment, techniques, and safety precautions that alpinists do, with certain specialized changes to account for the added difficulties of ascending vertical sheets of ice. In 1932 French climber Laurent Grivel added two extra front points to Eckenstein’s ten-point crampons. This enabled mountaineers to ascend more difficult and steeper climbs over icy routes. In the early 1970s American mountaineer and inventor Yvon Chouinard designed curved ice axe picks, which made it easier to drive axes into ice and secure them there. Ice climbers later created more radically drooped ice axe picks and ergonomically designed ice axe shafts, allowing them to venture onto continuously vertical, and even overhanging, frozen waterfalls.
A
Forms of Ice
Climbers encounter two natural forms of ice: alpine ice and water ice. Mountaineers and alpinists look out for alpine ice, while ice climbers deliberately search for water ice. Alpine ice is composed of large sheets of snow on mountainsides that over time have melted and refrozen. Water ice occurs at lower altitudes on frozen waterfalls, where it can take the shape of toothy icicles, steep curtains and pillars, free-standing columns, and thin veneers over rock. Whereas some alpine climbers regard ice as an obstacle to be overcome in the course of making a longer ascent, ice climbers seek out ice to pit themselves against its verticality and physical difficulty. Ice climbs are therefore shorter than alpine ascents, but they can be more taxing.
B
Ice Climbing Equipment and Technique
Ice climbers use an array of sharply pointed tools, notably 12-point rigid-frame crampons, two ice axes, and ice screws. An ice climber begins an ascent by kicking and securing the front points of each crampon in the ice. The climber then centers his or her body weight over the front points and concentrates on securing the ice axes. The climber swings one axe overhead and lodges it firmly into the ice, then does the same with the other. Then the climber pulls up and resecures the crampons slightly higher. The climber repeats this technique over and over, moving higher with each step.
To protect against falls, ice climbers anchor an ice screw every 5 to 10 m (16 to 33 ft), attaching their rope to the ice screw. They hand-screw the ice screws or twist them in using an axe pick. The ice screw anchors and the rope work together to reduce the danger of falls. For safety, climbers try to avoid breaking off large pieces of brittle ice with the ice axe. These ice chunks and shards can be sharp and can cause injuries.
V
ROCK CLIMBING
As alpine climbing developed in the European Alps in the early 20th century, French and German mountaineers sought out new challenges by training on cliffs and boulders near their homes. The earliest documented rock climb done for sport (not for military reconnaissance or scientific inquiry) was the 35-m (115-ft) high Nape’s Needle in the Lake District of England, which W. P. Hasket-Smith climbed alone on June 27, 1886. The first documented rock climb in North America was made in 1910 on a portion of Mount Washington in the White Mountains of New Hampshire, although the mountain itself had been climbed much earlier.
Rock climbing is now practiced on cliffs with a wide range of heights. Areas may be relatively small crags of rock, large canyon sidewalls, or immense mountain faces. Granite, limestone, sandstone, metamorphosed schist, and gneiss are the five most popular rock types for climbing.
A
Rock Climbing Technique
Rock climbers train by bouldering, which means practicing difficult climbing moves on large boulders or small outcroppings of rock that are only several feet above the ground. Bouldering is relatively safe because climbers can jump back onto solid ground at any moment. Difficult and strenuous movements can therefore be rehearsed without the use of ropes and hardware.
When ascending cliffs that are less than 50 m (164 ft) high, climbers use a technique called top-roping. On a top-rope belay, the climber is anchored from above, so he or she is protected against a serious fall. Rock climbers generally use a standard 50-m or 60-m rope. Rock climbs higher than 60 m thus require more than one pitch, or rope length, to be scaled; this type of climbing is termed multipitch or continuous climbing.
Specific types of rock climbing movements include friction climbing (moving up smooth, relatively low-angled rock slabs); face climbing (holding onto flakes, knobs and edges to ascend a sheer wall); crack climbing (jamming fingers, hands, arms, legs, feet, and toes into fissures in the rock); and overhang climbing (expending quick, calculated bursts of energy and muscle to swing past overhangs).
Strength is a major aspect of rock climbing, but it is not the most important physical requirement. Experienced climbers focus more on endurance, muscle coordination, flexibility, finesse, and excellent balance. On vertical and overhanging cliffs, moving smoothly up the rock, staying relaxed, and being mentally confident are equally vital to success.
There are two main types of rock climbing: free climbing and aid climbing. In its most basic form, a free climb is the unsupported ascent of a cliff face. Climbers use their fingers to grip flakes, edges, and cracks in the surface, while sticky rubber-soled shoes give support. The climber employs rope or other forms of protection, but only as a precaution to prevent a serious fall. The pieces of protection are never used to rest on, or for advancement. As soon as a climber uses equipment for support, he or she is no longer free climbing. The climber will then descend again to the last resting point where no support was used and reclimb the problematic section.
In aid climbing (also known as artificial climbing), climbers ascend pitches while using rope and hardware to support their body weight. Aid climbers also use a number of tools, including pulleys to move gear up the rock wall and étriers, or slings, to rest in. On climbs that require two or more days, climbers also use a portaledge. This easy-to-assemble device made of poles and shock-cords forms a rigid nylon floor and waterproof tent. The portaledge hangs from anchors placed in the rock wall and enables climbers to sleep and rest in a comfortable position, even though they may be hundreds or thousands of feet off the ground.
Rock climbing routes are named and assigned a difficulty rating by the first team of climbers to ascend a particular route. In the United States, free climbs are graded using decimal ratings, which range from 5.0 (easiest) to 5.14 (most difficult). In guidebooks the climb’s name is also accompanied by a commitment rating, which indicates the climb’s seriousness and how many hours or days it will take a team of two average-ability climbers to complete the route. Commitment ratings are given in Roman numerals from I (several hours) to VI (difficult climbs in remote locations). A similar scale (A1 to A5) is used when evaluating aid-climbing routes.
B
Rock Climbing Equipment
Rock climbing shoes resemble toughened ballet slippers, made of supple leather or synthetic materials. They have sticky rubber soles, and toes and heel-liners made of rubber. All climbing shoes and slippers should be fitted snugly around the foot. Climbers use gymnastic chalk (magnesium carbonate) to dry sweat from their hands and fingers while climbing. The white powder is carried in a small pouch called a chalk bag that is attached to the climber’s harness.
Because rock climbing requires plenty of innovative, supple movements, clothing should be lightweight, comfortable, and nonrestricting. T-shirts, shorts, and tights made of cotton, Lycra-cotton blends, and other synthetic materials are popular. Rock climbers also use athletic tape to protect fingers, knuckles, and wrists during difficult climbs.
VI
HISTORY
People have long climbed mountains for necessary daily activities such as retrieving lost animals and hunting, but technical climbing as a sport has a much shorter history. The sport’s history is often described in terms of first ascents, the conquering of previously unscaled mountains or, on mountains that have already been climbed, the accomplishment of previously untried and unclimbed routes.
After the ascent of Mont Blanc in 1786, people began to organize expeditions to make first ascents. Some of the most challenging mountains were found in the Himalayas of Central Asia, which contain many of the world’s highest peaks. In 1953 New Zealand climber Sir Edmund Hillary and Sherpa Tenzing Norgay made the first ascent of the world’s highest mountain, the Himalayan peak Mount Everest (8,850 m/29,035 ft). A year later Italian mountaineers Achille Compagnoni and Lino Lacedelli ascended the world’s second highest mountain, K2 (8,611 m/28,251 ft), which is also in the Himalayas.
As more of the world’s mountains were climbed for the first time, mountaineers sought to challenge themselves by using more difficult routes and by climbing with less assistance from climbing partners. In 1978 Italian mountaineer Reinhold Messner and Austrian climber Peter Habeler became the first to scale Everest without bottled oxygen. Two years later Messner returned to climb Everest completely alone and without oxygen.
Ascents in the late 20th and early 21st century became even more daring, and some climbers attempted to surmount groups of related summits. In 1985 American climber Dick Bass became the first mountaineer to climb the highest mountain on each of the seven continents, collectively referred to as the Seven Summits. In 1986 Messner finally completed his goal of climbing the 14 highest mountains in the world—a feat that took him 17 years to accomplish. All are higher than 8,000 m (26,000 ft) and are located in Nepal, Pakistan, China, and Tibet. Ed Viesturs became the first U.S.-born climber to accomplish this feat when he reached the summit of AnnapÅ«rna in May 2005. All of Viesturs’s 14 climbs, made over a period of 16 years, were completed without the benefit of bottled oxygen.
VII
RECENT DEVELOPMENTS
In recent years, well-publicized successes and tragedies in mountaineering activities, and improvements in climbing equipment, have given rise to an increased number of mountain climbers worldwide. The sport’s popularity has led some countries to require mountaineers to purchase climbing permits. Himalayan expeditions must also pay an environmental bond to guarantee that they will remove all of their waste at the conclusion of their trip.
Environmental efforts are underway at many rock climbing areas, where local climbers participate in an annual cleanup day to maintain approach trails, wash gymnastic chalk off the rock, and pick up litter. In the United States, placement of equipment that damages the rock is regulated on state and federal lands. The Access Fund is the national organization that helps climbers gain access to climbing areas and also assists with environmental problems associated with cliffs in the United States.
Beginning in the 1980s indoor rock-climbing gyms have played a key role in introducing large numbers of people to climbing, featuring short climbs in a controlled setting. However, making the transition to climbing outside is not always easy. New skills and judgment calls are required outdoors, because real cliffs are subject to bad weather and other hazards such as loose rock and falling stones.
In the late 20th century, climbing competitions became popular with rock climbers and ice climbers of all ages and skill levels. Regular competition climbing is judged on how high the climber can ascend within a specified period of time. Speed climbing competitions pit climbers against a clock to see how fast they can scale a wall. Local climbing gyms and clubs sponsor competitions, as do national organizations such as the American Sport Climbing Federation.
Internationally, mountaineers, ice climbers, and rock climbers are represented by the Union Internationale des Associations d’Alpinisme (UIAA). Since its founding in 1932, the UIAA has grown to represent about 80 associations in about 60 countries. As mountain climbing’s popularity rose dramatically in the 1980s and 1990s, the UIAA’s role in mountain safety, education, and environmental policy also increased. In the United States, the American Alpine Club, the Appalachian Mountain Club, the Colorado Mountain Club, and the Sierra Club are only a few of the organizations that have also addressed these issues. These organizations also offer instructional programs in climbing and provide an opportunity to meet fellow enthusiasts.

Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
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Magic

Kamis, 28 Oktober 2010

Magic (conjuring)
I
INTRODUCTION
Magic (conjuring), art of entertaining with tricks that are in apparent violation of natural law. The principles of deception that magicians use are psychological; the methods are manipulative and mechanical. The psychological principles are misdirection, suggestion, imitation, and concealment. The spectators do not see everything that happens, and they believe they see things that do not happen. Such faulty perception leads to false assumptions, fallacious logic, and, in the end, to the conclusion that the performer has achieved an impossible result.
Sleight of hand, that is, deception by manual dexterity, consists in the performance of certain actions that are not perceived because they are concealed, or are misconstrued because they imitate some innocent, natural action. In the more difficult magical tricks, the performer employs sleight of hand without the use of special apparatus. Mechanical methods involve the use of camouflaged apparatus that the audience sees but does not comprehend and of apparatus that is not seen. The tricks employing apparatus include stage tricks in which objects appear, disappear, change, float on air, survive mutilation, or penetrate solid barriers.
Mentalism is a branch of conjuring in which the magician simulates telepathy, clairvoyance, and precognition (see Psychical Research).
II
HISTORY
The earliest written records indicate that a distinction has probably always been made between magicians who are entertainers and the tribal witch doctors and medicine men who claimed that their incantations and spells could control nature and human destiny. The first magicians of recorded history were those of ancient Egypt. The Egyptian magician Dedi, who lived about 2700 bc gave a performance in which he decapitated two birds and an ox and then restored their heads. Other Egyptian magicians were noted for their skill with the trick of the cups and balls. In this trick small balls seem to pass invisibly from one inverted cup or bowl to another. Finally, they are converted into larger spheres or such unexpected things as oranges or live baby chicks.
Sleight of hand with coins, dice, and, later, playing cards added variety to the performances of medieval magicians. The tricks of the cut and restored string and of thrusting a dagger through the arm without injury were performed in taverns and in marketplaces.
III
FAMED MAGICIANS
The first magician known to have performed in North America was an anonymous member of the retinue of the Spanish explorer Hernán Cortés. Jacob Meyer, whose professional name was Philadelphia, was the first American to achieve an international reputation as a conjurer.
The Italian Giuseppe Pinetti was the most imitated magician of the 18th century. His repertory included automatons, that is, machines that operated by themselves; pretended second sight; and novel tricks with apparatus.
The British magician John Henry Anderson, called the Wizard of the North, was a master publicist. Among his promotional schemes were elaborate street parades, flamboyant posters, and advertisements stenciled on pavements. His tricks frequently related to current news topics, and he often denounced as frauds persons professing supernatural powers.
The French magician Jean Houdin, a clockmaker who at the age of 40 became a professional magician, revolutionized the art of magic with his ingenious stage mechanisms and effective presentations. His textbooks were the first to treat magic scientifically, and he was the first to use electricity as an aid in stage mysteries.
Another French magician who developed original techniques was Joseph Buatier, known as Buatier De Kolta. Two of his outstanding inventions were the vanishing birdcage, a trick in which a live canary and a metal cage disappeared at his fingertips, and the expanding die, in which a 20-cm (8-in) cube suddenly increased 20 times its original size and was then lifted to disclose a seated woman.
The popular conception of a magician as a slender man with a mustache, goatee, and satanic air probably started with the Herrmann family, for the famed magicians of this family all answered to the description. Carl Herrmann, a native of Vienna, won acclaim in Europe and America. His younger brother, the American magician Alexander Herrmann, called Herrmann the Great, and his nephew Leon Herrmann also toured extensively in America and abroad.
John Maskelyne and his partner David Devant, the leading British magicians of their day, presented many of their acts in the form of skits or short plays. Their London theater was world famous. The American magician Harry Kellar took his show, which included sleight of hand, illusions, and the duplication of feats performed by alleged spirit mediums, around the world. He was the best-known magician in America when he retired in 1908. His successor, the American magician Howard Thurston, performed throughout the U.S. for 28 years. His show included such spectacular features as the vanishing automobile, the Indian rope trick, and levitation. Harry August Jansen, who used Dante as his professional name, and Harry Blackstone carried on the tradition.
Another American magician, Harry Houdini, won world renown by effecting sensational escapes from police handcuffs, straitjackets, and prison cells. He frequently jumped, in shackles, from bridges and released himself underwater. The last years of Houdini's life were devoted to a relentless campaign against fraudulent mediums. His thorough knowledge of deceptive techniques enabled him to expose their methods.
One of the greatest box-office attractions in the history of magic was the feat of appearing to saw a woman in half. In the first performance of this act in London in 1921, the British magician Percy Tibbles, whose professional name was P. T. Selbit, cut through a box that contained a woman assistant. She emerged unharmed. Several months later Hyman Goldstein, whose professional name was Horace Goldin, presented an even more puzzling variation of the act in New York City. The head, hands, and feet of his assistant were in full view throughout the operation. Later Goldin discarded the covering box, and, using a power-driven saw, performed the sawing-through and restoration in full view.
During the 1950s magicians began to reach larger audiences than ever through television. Among the leading magicians who made television appearances were the Indian illusionist P. C. Sorcar; the British performer Richard Pitchford, whose pantomimic sleight of hand act was widely imitated; and the American magicians Milbourne Christopher, whose televised acts included making an elephant disappear and levitating an assistant, and Mark Wilson, who had his own weekly program.
During the 1970s there was a resurgence of interest in magic. The German magician Siegfried Fischbecker and his American assistant Roy Horn, who specialized in making tigers and other large animals disappear, performed in acclaimed productions in Las Vegas, Nevada. Doug Henning, a Canadian magician, and the American David Kotkin, known as David Copperfield, developed considerable theatrical skill as they performed in films and stage musicals as well as on television. Harry Blackstone, Jr. carried on his father's achievements with large, lavishly produced touring shows and a Broadway show.
IV
MAGICIANS' ASSOCIATIONS
Noteworthy associations of magicians, with estimated membership in the mid-1980s, include the Society of American Magicians (5900) and the International Brotherhood of Magicians (10,500). Approximately 500 professional and 70,000 amateur magicians perform in the U.S.


Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
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In-Line Skating

In-Line Skating
I
INTRODUCTION
In-Line Skating, activity in which people glide over a surface on in-line skates, which are lightweight boots with three to five wheels attached in a line under the foot. The activity is also known as rollerblading, a name that comes from the company Rollerblade, Inc., which was the first firm to design and sell mass-produced in-line skates.
Some people participate in in-line skating as off-season training for winter sports such as Nordic skiing and ice hockey, but most do it for its own sake, as exercise and for enjoyment. Enthusiasts can in-line skate indoors in arenas and outside wherever smooth pavement or concrete is found. Popular locations include trails, sidewalks, and skate parks (areas specially designed for traffic-free skating activities).
Understanding in-line skating’s basic techniques make the sport fun and easy. To learn these techniques, beginners should take a class offered through a store or organization. Once they have mastered the sport’s basic skills, advanced skaters often participate in one of the many forms of competitive in-line skating, such as aggressive skating, racing, and roller hockey.
II
BASIC TECHNIQUES
Before they in-line skate for the first time, beginners should assess the skating surface for slight hills, small cracks, debris, water, and oil. Skaters should avoid these obstacles because they can make the skate unexpectedly slip or slide. Beginners should also skate in a traffic-free area to avoid collisions with cars, bikes, pedestrians, and other skaters.
Striding, stopping, and turning are the basic techniques each skater should learn first. For any maneuver, skaters should look ahead and keep the knees and ankles slightly bent. The position of a skater’s elbows and hands is also important, as maintaining both arms in front of the body provides better balance.
Skaters move and create speed by using a technique called striding. To stride, skaters balance on one foot while pushing off with the other. They then glide and repeat the technique with the opposite foot. Advanced skaters develop a rhythm of equal and forceful strides that move them forward in a straight line.
Skaters can use several methods when they want to stop. Using the heel brake, which is a hard rubber pad attached to the back end of the right skate, is the most common. To use the heel brake, a skater moves the right foot slightly in front of the body while balancing on the other foot for support. Then, with knees bent, the skater pulls the right toe up, forcing the brake pad to make contact with the ground. With the brake gently engaged, the skater can come to a controlled stop.
Some skaters prefer to remove the heel brake from their skates because it gets in the way when doing advanced tricks. Without a heel brake, several other methods can be used to stop. Two of the most common are the t-stop and the powerslide. In a t-stop, a skater drags one foot behind the body, perpendicular to the forward foot. When the wheels of the dragged skate come in contact with ground, they cause the skater to slow down and eventually stop. A powerslide is an extremely short and quick turn that results in a full stop. The skater abruptly pivots and turns sideways, while maintaining balance. The quick turn causes the skates to slide just a few inches before stopping.
Turning is the third basic skill in in-line skating. To turn right, a skater moves the right foot slightly forward and points both feet right. This pulls the skater’s right skate onto its outside edge and left skate onto its inside edge, guiding the skater into the turn. To turn left, the skater follows a similar process, but puts the left foot forward and points both feet left.
A specialized type of turn, called a crossover, is used to accelerate through corners when balance is critical. Turning to the right, the skater lifts the left skate slightly off the ground and places it on the right side of the right skate. The skater simultaneously pushes on the outside edge of the right foot. This crossing motion and foot pressure helps the skater turn the corner in a controlled manner.
III
ADVANCED TECHNIQUES
Advanced skaters use special techniques when they participate in street skating, also called aggressive skating. Street skating involves doing tricks and stunts by using obstacles such as curbs, handrails, and stairs. The curb launch and grinding are common street skating techniques.
Curb launches are jumps off of elevated surfaces such as curbs. As they approach the curb, skaters keep their knees bent. They then lift their feet as they pass over the curb and fly into the air. Skaters absorb the shock of the landing by bending at the ankles, knees, and hips.
Grinding involves jumping on curbs, rails, or other objects that have a thin edge. The skater begins by skating toward the obstacle to pick up speed. The skater then jumps onto the edge, positioning one or both skates perpendicular to the edge and the desired direction of travel. The speed of travel allows the skater to slide sideways across the object.
Vert skating, short for vertical skating, is another type of advanced skating. It involves skating in a structure called a half pipe, which is shaped like a trough and can rise as high as 2 m (6.5 ft). Skaters ride the curves of the trough to propel themselves into the air and remain airborne for a few seconds. While in the air, skaters can perform a variety of tricks, such as turning their body in a half circle (called a 180) or a complete circle (a 360). Flips are also popular, as is a maneuver called a foot grab, in which the skater extends the body horizontal and grabs the feet. The most difficult maneuver, however, is dropping in, or returning back down onto the trough’s side when landing.
Launch ramps and fun boxes (obstacles, including launch and landing ramps, stairs, curbs, and rails, specially made for in-line skating and skateboarding tricks) can be found at designated skating areas or skate parks. The versatility and angle of ramps and box construction allow skaters to practice and perform many different types of tricks. Because skate parks prohibit cars, bikes, and other traffic, they are safe areas to enjoy skating.
IV
EQUIPMENT
Because most skating takes place on concrete or other hard surfaces, in-line skaters should always wear protective gear, primarily wrist, elbow, and knee guards and a helmet. This protects skaters in case they crash.
There are several different types of skates. Most people prefer a four-wheeled model that offers adequate support around the lower leg and a snug fit. Skaters should make sure that the skate fits correctly, because improper fit can cause blisters and discomfort on the feet, ankles, and lower legs.
On average, a pair of skates weighs between 2 and 3 kg (4 and 7 lb). Most skates are composed of a hard plastic outside shell and a boot liner. The shell closes over the foot using a combination of laces and buckles. Many skaters prefer a simple closure system that has laces on the lower portion of the skate and a buckle at the top. The boot liner is made of a soft, padded, cloth portion that fits inside the outer shell. Boot liners should be vented, which keeps the feet cool by allowing perspiration to escape during strenuous workouts or long trips.
Attached to the bottom of each skate is the wheel frame. The frame houses from three to five wheels. The wheels are lined up between two carbon-fiber composite runners, which keep each wheel fixed in a straight line. Most frames are permanently attached to the outside plastic shell, but some skates allow skaters to switch between longer and shorter frames. Shorter frames are more maneuverable while practicing tricks. Longer frames house more wheels and allow for smoother, faster skating.
Wheels are made of urethane, a durable material that absorbs shock. Wheels come in varying sizes and are generally grouped into two categories: large and small. Large wheels are between 76 mm and 80 mm (2.99 and 3.15 in) in diameter and are more stable at higher speeds. Small wheels are between 70 mm and 72 mm (2.76 and 2.83 in) in diameter. The benefit of smaller wheels is the added maneuverability they allow. The proper wheel size therefore should be based on the performance requirements: speed or maneuverability.
Some skaters use additional equipment for street skating and vert skating. Power straps that wrap around the feet and ankles are used to provide extra support when landing jumps and drop-ins. Large, heavy-duty protective pads for knees are also available.
V
COMPETITION
In-line skating competitions include racing, aggressive skating, and roller hockey. Information about these forms of competition can be found at stores that sell in-line skating equipment and at local park and recreation departments. Each form of competition has several different levels, from beginner to professional.
The simplest form of in-line skate competition is racing, on circuits of various lengths, from 1 to 50 km (0.6 to 31 mi). Racers compete one on one, in larger groups, and in relays. Sometimes two skaters compete in slalom runs, where they race a similar obstacle course at the same time. Another popular form of racing is speed skating. In-line speed skating resembles the speed skating that is practiced on ice, where participants race on a relatively short oval track.
Nearly all professional aggressive skaters compete in events sponsored by the Aggressive Skater's Association (ASA), which is the world’s largest sanctioning body for aggressive skating. Competitions are held in skate parks throughout the world. Generally, skaters are given two 60-second or 90-second runs during which they blend free form skating tricks with compulsory moves on rails, ramps, and half pipes. ASA judges score each skater’s performance based on style, difficulty, and creativity.
Roller hockey is another popular form of competition. The rules are similar to those of ice hockey, but there is less physical contact. Roller hockey is played with a small, hard, plastic ball instead of a hockey puck. Many parks and recreation departments organize amateur league play. Roller Hockey International and USA Hockey Inline are governing organizations that oversee advanced amateur and professional roller hockey leagues.
VI
HISTORY
In-line skating dates from the 1700s, when people in the Netherlands fastened wooden wheels to shoes. In-line skating failed to become a popular recreational activity, however, because wheels wore down quickly, and only elite athletes used the skates in speed competitions. In-line skates gave way to the design of traditional roller skates. Roller skates have a set of two wheels both at the front and the back of a boot. This design makes it easier for people to remain balanced while rolling.
During the 1980s a young American entrepreneur named Scott Olsen wanted to create a way to train for ice hockey during the off-season. He developed the first modern in-line skates by putting together a metal frame, durable urethane wheels, and a heel brake. Olsen later founded Rollerblade, Inc., and began producing in-line skates for general recreation. With innovations like polyurethane boots and wheels, in-line skating became an easy, enjoyable activity available to many people. Today there are more than 30 in-line skate companies that produce skates, protective gear, and apparel specifically designed for recreational skaters.

Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
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Hunting

Hunting
I
INTRODUCTION
Hunting, sport of pursuing and killing wild game animals in order to provide food, or simply for the thrill of the chase, or for the enjoyment of outdoor life. People have been hunting since prehistoric times to provide themselves and their families with food, fur and leather clothing, and hides for shelter. With the development of agriculture, animal husbandry, and, eventually, manufacturing, hunting gradually diminished in importance as a means of survival. Because of its challenge and pleasure as a sport, however, hunting has remained a popular activity even in modern times.
II
HISTORY OF HUNTING
The leisured nobility of ancient Egypt, Greece, and Rome enjoyed hunting for sport. Greek historian Xenophon argued that hunting is an asset to society, in that the recreation promotes the well-being and health of the hunter. The first laws designed to conserve game animals were not instituted until the 13th century, when Kublai Khan, emperor of the Mongols, forbade his subjects to hunt during animal breeding seasons. During the Middle Ages (5th century to 15th century) the feudal lords of Europe imposed extensive restrictions on hunting, effectively limiting the taking of game to the ruling classes. Stag hunts with hounds and horses and the pursuit of game birds with trained falcons (see Falconry) were popular pastimes of the nobility.
The invention of gunpowder in the 14th century and the perfection of the matchlock rifle in the 15th century drastically changed methods of hunting. Whereas the trap and snare, the bow and arrow, and falcons and hounds had previously been used, rifles now facilitated the bringing down of fleeing birds and animals at greater distances and in greater numbers.
Today, most hunters use rifles and shotguns to pursue their sport; shotguns and .22-caliber rifles are generally used for small game such as squirrels and rabbits, and larger caliber rifles are employed for animals such as deer and elk. For game birds such as ducks, geese, doves, and pheasant, 12- and 20-gauge shotguns are used. Claiming that primitive weapons make the hunt more challenging, many hunters now have gone back to the use of bows and arrows, especially for deer (see Archery), and some use muzzle-loading rifles.
III
HUNTING METHODS
The method of hunting depends on the animal hunted. Hunters of ducks and geese hide in blinds, or camouflaged areas, and try to lure birds into shotgun range by using waterfowl calls and wooden decoys. Hunters of grouse and pheasant walk through woods and fields and use trained dogs to locate and flush out game within gun range (see Field Dog). Wild turkeys are hunted by camouflaged hunters using mouth- and hand-operated turkey calls.
Hunters of larger game—for example, deer—employ four techniques: still-hunting, stand hunting, stalking, and driving. Still-hunting, used when game is known to be in the area but no specific animal is in sight, involves following tracks and looking for signs such as antler-shredded trees or urination areas. The hunter moves quietly, on the alert to shoot should the quarry be sighted. When stand hunting, the hunter takes position along a game trail and waits for the quarry to go by. Stalking is done when a game animal is sighted but is out of range. In this case, the hunter tries to move into rifle range while remaining hidden and downwind of the quarry. In driving, or beating, a group of hunters moves through an area deliberately making noise and trying to frighten game animals in the direction of other hunters.
IV
GAME AND GAME MANAGEMENT
Game animals are hunted throughout the world. In North America, deer, elk, bear, pronghorn, caribou, rabbit, squirrel, duck, goose, pheasant, and wild turkey are hunted. Among the animals hunted in Asia are elephant, tiger, wild sheep, deer, bear, rabbit, waterfowl, and pheasant. African safari-hunting offers opportunity to bag a diversity of game: Cape buffalo, elephant, lion, antelope, and duck and other wild fowl. European hunters generally go out for wild boar, fox, red stag, rabbit, and various game birds. Jaguar, peccary, deer, duck, dove, and turkey are popular quarry in Central and South America.
Unregulated hunting has at various times threatened the existence of some game animals. Prime examples of this occurred in the United States in the 19th century, when egrets were decimated for their plumes, used in millinery. Buffalo herds (see Bison) that once numbered in the millions were also virtually wiped out by hunters intent on profit and enjoyment; by 1895 only 400 buffalo remained in the country. Hunters took their toll on other wildlife as well. Pronghorn, deer, and mountain sheep were decimated to feed the growing population in the West. In the East, waterfowl populations plummeted as hunters armed with cannonlike guns wiped out entire flocks in one shot and then shipped the birds to restaurants to satisfy exotic tastes. Some game birds, such as the passenger pigeon and the heath hen, were hunted into extinction by people who believed the game supply to be infinite.
Public outcries eventually forced some states in the 19th century to pass laws protecting certain animals. During an expedition to the Yellowstone region in 1871, photographer William Henry Jackson and artist Thomas Moran depicted the countryside. These images persuaded the American public and the U.S. government to preserve the area. President Ulysses S. Grant signed a bill creating Yellowstone National Park in 1872. The setting aside of other such national parks, where wildlife may not be hunted, soon followed (see National Park Service). In 1900, Congress passed the Lacey Act, which put a damper on commercial market hunting by regulating the interstate shipment of game. Other federal and state laws were passed in subsequent years, establishing hunting seasons, limiting the daily allowable kill of game per hunter, outlawing unfair and inhumane hunting methods, and making it illegal to hunt species in danger of becoming extinct. See also Endangered Species.
With strictly enforced regulations, the number of game animals began to increase. This, in itself, caused problems. As human settlements spread across the country, predatory animals such as the wolf and grizzly bear were either killed off or forced into remote regions. Unchecked by these natural enemies and protected by hunting laws, game animals such as deer and elk reproduced so rapidly that they would eat all the available food in their range, and then many would die of starvation.
In 1933 American biologist Aldo Leopold developed a theory that each unit of habitat can support only so many animals of a given species, and that excess animals must be cropped by hunters or allowed to die. Since that time, game laws have been designed so that hunters crop the annual surplus of game animals without threatening actual game populations. Such regulations, which make hunting a crucial part of game management, have allowed wildlife to thrive in the United States. Other nations, notably those in Africa, have also followed this precept, but nonetheless illegal poaching for food or trophies remains a problem.
V
WILDLIFE ORGANIZATIONS
Many organizations in the United States are engaged in game management. On the federal level, the U.S. Fish and Wildlife Service oversees national conservation efforts. Each state also has a fish and game department, and private groups, including the National Audubon Society, the National Wildlife Federation, and Ducks Unlimited, support conservation programs. In Canada, conservation and game-management organizations include the Canadian Wildlife Service on the national level, wildlife divisions on the provincial level, and the Canadian National Sportsmen's Fund on the private level.

Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
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Games

Rabu, 27 Oktober 2010

Games
I
INTRODUCTION
Games, activities or contests governed by sets of rules. People engage in games for recreation and to develop mental or physical skills.
Games come in many varieties. They may have any number of players and can be played competitively or cooperatively. They also may involve a wide range of equipment. Some games, such as chess, test players’ analytic skills. Other games, such as darts and electronic games, require hand-eye coordination. Some games are also considered sports, especially when they involve physical skill.
II
CATEGORIES OF GAMES
Games may be classified in several ways. These include the number of players required (as in solitaire games), the purpose of playing (as in gambling games), the object of the game (as in race games, to finish first), the people who play them (as in children’s games), or the place they are played (as in lawn games). Many games fall into more than one of these categories, so the most common way of classifying games is by the equipment that is required to play them.
Board games probably make up the largest category of games. They are usually played on a flat surface made of cardboard, wood, or other material. Players place the board on a table or on the floor, then sit around it to play. In most board games, pieces are placed on the board and moved around on it. Dice, cards, and other equipment can be used.
In strategy board games, pieces are placed or moved in order to capture other pieces (as in chess or checkers) or to achieve such goals as gaining territory, linking pieces to one another, or aligning pieces together. Other major groups of board games include race games (such as backgammon), word games (Scrabble), games of deduction (Clue), trivia games (Trivial Pursuit), party games (Pictionary), family games (Life), financial games (Monopoly), sports games (Strat-O-Matic Baseball), action games (Operation), and games of conflict (Risk).
Many games fall into more than one category. The board game Life, for example, has elements of race games, and Trivial Pursuit is often played at parties. Other types of board games include topical games, which can be based on currently popular movies, television programs, or books; and simulation games, which range from historical war games to civilization-building games.
Role-playing games, which can be played without boards or with playing fields drawn by hand on paper, are often considered a distinct game category. In these games, each player assumes the role of a character with particular strengths and weaknesses. Another player known as the gamemaster leads the character-players through adventures. The most famous role-playing game is Dungeons & Dragons (now called Advanced Dungeons & Dragons), which was invented in the 1970s.
Some games, such as billiards and table tennis, are played on larger surfaces than board games, typically tables with legs. These table games also require different kinds of equipment from board games. In billiards, players use a cue stick to knock balls into one another. Table tennis players use paddles to hit a light ball back and forth over a net strung across the table.
Card games require a deck of cards, and sometimes paper and pencil (or occasionally other equipment, such as a cribbage board) for keeping score. Many popular games, including poker, bridge, and rummy, call for a standard deck of 52 playing cards. Some card games, such as canasta, use more than one deck or a larger deck. And other games use a deck from which certain cards have been removed, or decks with cards designed specifically for the game.
The major kinds of card games include trick-taking games, in which players try to take (or avoid taking) specific cards; melding games, in which players try to form winning combinations with their cards; betting games, in which players wager on the outcome; and solitaire games, which are played alone. A new category, collectible card games, became an overnight sensation in 1993 with the publication of Magic: The Gathering. In Magic and similar games, players buy a starter set of cards that they use to compete against other players. They can supplement the starter kit with additional purchases of random assortments of cards.
Tile games can be similar to card games, but they use pieces made of harder materials, such as wood, plastic, or bone. Popular tile games include Mah Jongg and dominoes. Dice games involve throwing a set of dice in an attempt to achieve certain combinations or totals. Paper and pencil games use only paper and pencil. Two such games, tic-tac-toe and dots-and-boxes, are among the first games that many children learn. Target games, in which players aim at a target, are tests of hand-eye coordination. Examples of target games are marbles, horseshoe pitching, and bowling.
Electronic games (video games and computer games) grew in popularity in the late 20th century, as the power of computers increased. In most electronic games, players use a keyboard, joystick, or some other type of game controller. Video games are played on specially designed arcade machines, handheld devices, or systems that are hooked to television screens. Computer games are played on home computers. With electronic games, the computer itself can serve as the opponent, allowing people to play traditional games such as chess or bridge against the computer.
III
HISTORY
Games have been played for thousands of years and are common to all cultures. Throughout history and around the world, people have used sticks to draw simple game boards on the ground, making up rules that incorporate stones or other common objects as playing pieces. About 5000 years ago people began to make more permanent game boards from sun-dried mud or wood. One of the earliest games, called senet, was played in ancient Egypt. Like many early games, senet had religious significance. Pictures on the board squares represented different parts of the journey that the ancient Egyptians believed the soul made after death.
Some of the oldest board games may have evolved from methods of divination, or fortune-telling. The game of go, which many experts regard as the finest example of a pure strategy game, may have evolved from a method of divination practiced in China more than 3000 years ago, in which black and white pieces were cast onto a square board marked with symbols of various significance. Go also involves black and white pieces on a board, but players deliberately place them on intersections of lines while trying to surround more territory than the opponent.
Many modern games evolved over centuries. As games spread to different geographic regions, people experimented with rules, creating variants and often changing the original game forever. The name mancala applies to a group of ancient Egyptian mathematical games in which pebbles, seeds, or other objects are moved around pits scooped out of dirt or wood. As the game spread through Asia, Africa, and the Americas, players developed local variations that are still played today. Two such variations are sungka, from the Philippines, and mweso, from Uganda.
Chess, xiangqi (Chinese chess), and shogi (Japanese chess) are among the most widely played board games in the world. Although quite different, all three are believed to have evolved from a common ancestor—either a 6th-century game played in India or an earlier game played in China. Over the centuries, chess spread westward to the Middle East and into Europe, with rules changing frequently. The game also spread eastward to Korea and Japan, resulting in very different rule changes.
For most of human history, a game could not gain much popularity unless it was fairly easy for players to make their own equipment. The invention of printing (which occurred in the mid-1400s in the West) made this process easier, but it was not until the advances of the 18th-century Industrial Revolution that it became possible to mass-produce many new varieties of games. Twentieth-century technological advances such as the invention of plastic and the computer revolution led to the creation of more games, and more new kinds of games, than in all previous centuries combined.
IV
RECENT TRENDS
In recent years improvements in CDs (compact discs) and in other aspects of computer technology have brought about entire new categories of games that grow more sophisticated each year. Computer adventure games, which as recently as the early 1980s consisted almost entirely of text, can now feature sophisticated graphics and movie-like animations using human actors.
In the 1990s the Internet opened up the possibility of playing games with people in all parts of the world. Internet clubs have sprung up for many kinds of games, and many of the newest computer games now come with user interfaces for online play.

Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.

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