The processes of recording audiotape and videotape work on the same principle. An audio or video recording head is a small electromagnet containing two coils of wires separated by a gap. An electrical current passing through the wires causes a magnetic charge to cross the gap. When tape coated with metal particles passes through the gap, patterns are set on the material. On audiotape, each syllable, musical note, or sneeze sets down its own distinct pattern. For videotape, which carries several hundred times as much information as audiotape, each image has its own pattern.

     In the late 1940s and early 1950s, the explosive growth of television created an enormous demand for a way to record programs. Until links could be established through television lines or microwave broadcast relay, a blurry kinescope was the only means by which a network program could be recorded and replayed on different local television stations. As a result, television programs were unstable, ephemeral events. Once transmitted electronically, they were, for the most part, lost in time and space, unavailable for repeated use as either aesthetic, informational, or economic artifacts.

     In 1951 engineers at Bing Crosby Enterprises demonstrated a black-and-white videotape recorder that used one-inch tape (tape size refers to tape width) running at 100 inches per second. At that rate, a reel of tape three feet in diameter held about 15 minutes of video. Crosby continued to fund the research, driven not only by a sense of commercial possibilities for videotape, but reportedly also by his wish to record television programs so that he could play golf without being restricted to live performances. Two years later, RCA engineers developed a recorder that reproduced not only black-and-white but color pictures. However, tape ran past the heads at a blinding 360 inches per second, which is 20 miles per hour. Neither machine produced pictures of adequate quality for broadcast. It simply was not possible to produce a stable picture at such a high tape speed.

     During this same period, Ampex, a small electronics firm in California, was building a machine on a differ­ ent principle, spinning the recording head. They succeeded in 1956 with a recorder the size of two washing machines. Four video heads rotated at 14,400 revolutions per minute, each head recording one part of a tape that was two inches wide. One of the engineers on the project, Ray M. Dolby, later became famous for his tape noise reduction process and his multisource theater sound system.

     The quality of Ampex recordings was such an improvement over fuzzy kinescope images that broadcasters who saw the first demonstration, presented at a national convention, actually jumped to their feet to cheer and applaud. The television industry responded so enthusiastically that Ampex could not produce machines fast enough. It was the true beginning of the video age.

     West Coast television stations could now, without sacrificing picture quality, delay live East Coast news and entertainment broadcasts for three hours until evening prime time, when most viewers reached their homes after work. By 1958 the networks were recording video in color, and by 1960 a recorder was synchronized with television studio electronics for the familiar film-editing techniques of the "dissolve" and "wipe."

     Large two-inch reel-to-reel Ampex machines survived for a generation before they were replaced by more compact and efficient one-inch reel-to-reel machines and three-quarter-inch cassette machines. By 1990 most of the bigger recorders had been retired.

     While U.S. companies were manufacturing two­ inch, four-head, quadruplex scan machines, Japanese engineers were building the prototype of a helical scan machine that employed a single spinning head. Toshiba introduced the first helical scan VTR machine in 1959. JVC soon followed. The picture quality produced by these machines would remain inferior to "quad" machines for another ten years, unsuitable for the broadcast industry. But the smaller, more user­-friendly helical scan machines, costing a fraction of the price of larger machines, quickly dominated the industrial and educational markets.

     In 1972 Sony introduced the Port-a-pak black-and­ white video recorder, weighing less than ten pounds. The tape had to be threaded by hand, but the Port-a­ Pak was an important step on the way to electronic news gathering, known in the television industry as ENG. The next big step, Sony's U-matic three-quarter­ inch tape machine, which played tape cassettes, eliminated physical handling of tape. CBS-TV News sent a camera team equipped with an Ikegami video camera and a U-Matic tape recorder to cover President Richard Nixon's trip to Moscow. News stories were soon being microwaved back to stations for taping or live feeds. Prior to these developments, the visual portion of news broadcasts had been produced on film. Videotape was the far superior medium for news. It needed no developing time, was reusable, and was more suited to the television's sense of immediacy. With the coming of videotape, television news editors replaced razor blades with electronic editing devices.

     With broadcasting, educational, and industrial mar­kets in hand, Japanese video companies turned their attention to the potentially vast home market. Hobbyists had already shown the way. With slightly modified portable reel-to-reel machines, they were taping television programs at home to play again later.

     Sony, whose research was led by Nobutoshi Kihara, had considered the home market from the start. Recognizing that not only television stations but viewers ought to be able to time-shift programs, Sony president Akio Morita said, "People do not have to read a book when it's delivered. Why should they have to see a TV program when it's delivered?" Sony introduced its half-inch Betamax machine in 1975. A year later, rival Japanese companies, led by JVC, brought out VHS machines, a format incompatible with Betamax. VHS gradually captured the home market. People at home could simply and inexpensively record television programs and could buy or rent tapes. At last it was possible to go to the movies without leaving home.

     Tape renting began when businessman Andre Blay made a deal to buy cassette production rights to 50 Twentieth Century Fox movies. Blay discovered that few customers wanted to buy his tapes, but everyone wanted to rent them. 

     The motion picture industry considered the videodisc a better way to bring a movie into the home, pointing out its sharper picture image, stereo sound, lower cost, and copy protection. However, the public wanted recording capability, not so much to copy rented films illegally as to record movies and television programs off the air for later playback. Videodisc players could not match the flexibility of videocassette recorders for time-shifting. In the battle over competing disc and tape formats, VHS tapes emerged the clear winner-at least in the first round.

     In the first decade of the 21st century, a little more than 100 years after motion pictures were invented, millions of users could make movies, aided by nonlinear editing machines and computer programs that became better and cheaper year by year. Video cameras found their way into schools as learning tools. The high school library is now often referred to as "the media center," and the video yearbook has joined the printed version. Even in elementary schools, curious fingers are pushing camera buttons.

     Videotape has also introduced specific changes at a very different level, expanding the production community in the professional arena. It is possible to produce a motion picture of technically acceptable quality at modest cost. For example, two young men barely out of college used videotape and nonlinear editing to make the feature film The Blair Witch Project; costing around $35,000 to produce, that movie has reportedly earned upward of $ 150 million. The phrase "desktop video" has become part of our language, often in relation to desktop publishing.

     Videotape has had wide impact everywhere on Earth, including remote villages, where inexpensive tapes bring in formation and entertainment. A truck carrying a videotape player, a television set, and a portable generator is not an uncommon sight in many parts of the world. People living as far from urban centers as the Kayapo of the Brazil rainforest and the Inuit of northern Canada have been introduced to video and have themselves produced tapes to argue for political justice and to record their cultural heritage.

     Several Third World governments have actively promoted videotape programs for adult education. For example, the Village Video Network in several countries provides an exchange for tapes on such subjects as farming, nutrition, and population control. International groups have given some villages video cameras and training to produce their own films, which are later shown to other villages.

     Another result of video diffusion has been a widening of video journalism capability. The taping of Rod­ ney King being beaten by members of the Los Angeles Police Department is just one example of how ordinary citizens are making a difference not only in news coverage but in the course of events. The potential for a video vigilantism by "visualantes" has not gone unnoticed, with its effects reaching not only journalism but law enforcement itself.

     Far less significant uses of videotape technology have also developed. Replacing the traditional matchmaker, for example, is the video dating club. Participants tell a video camera of their interests, their virtues, and the type of person they would like to meet. They look at other videotapes and their videotape is shown to prospects.

     Serious social and legal problems are also directly related to the easy use of this technology. Video piracy is rampant. A vast underground network feeds millions of illegal copies of videotaped movies throughout the world. The national film industries of a number of countries have been battered both by the pirating of their own films and by the influx of cheap illegal copies of Western films.

     Some of these issues may be resolved with the development of still newer technologies. For both the video and computer industries, the future of information storage and retrieval may lie not with tape but with such optical media as CD-ROM and DVD, which offer the advantages of high density, random access, and no physical contact between the storage medium and the pickup device. As with the earlier videotape "revolution," the television and film industries are now shifting their investments and altering their industrial practices to deal with the newer, digitally based devices. The results of these changes for consumers, educators, and journalists are not easily predicted, yet there is no question that all these groups will experience alteration in media use akin to that caused by the introduction of videotape.