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By the late 1990s videotape was familiar to most television viewers in developed countries. The videocassette was a central product throughout the home video market and in various formats was widely used as a consumer item for home recording. Despite these widespread and common uses, however, videotape is of relatively recent origin. Its immediate antecedent is, of course, audiotape.
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 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 fifteen 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 which 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.