Videocassettes

Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog signal or digital signal. Videotape is used in both video tape recorders (VTRs) or, more commonly, videocassette recorders (VCRs) and camcorders. Videotapes are also used for storing scientific or medical data, such as the data produced by an electrocardiogram.

Because video signals have a very high bandwidth, and stationary heads would require extremely high tape speeds, in most cases, a helical-scan video head rotates against the moving tape to record the data in two dimensions.

Tape is a linear method of storing information and thus imposes delays to access a portion of the tape that is not already under the heads. The early 2000s saw the introduction and rise to prominence of high quality random-access video recording media such as hard disks and flash memory. Since then, videotape has been increasingly relegated to archival and similar uses.

The electronics division of entertainer Bing Crosby's production company, Bing Crosby Enterprises (BCE), gave the world's first demonstration of a videotape recording in Los Angeles on November 11, 1951. Developed by John T. Mullin and Wayne R. Johnson since 1950, the device gave what were described as "blurred and indistinct" images using a modified Ampex 200 tape recorder and standard quarter-inch (0.6 cm) audio tape moving at 360 inches (9.1 m) per second. A year later, an improved version using one-inch (2.6 cm) magnetic tape was shown to the press, who reportedly expressed amazement at the quality of the images although they had a "persistent grainy quality that looked like a worn motion picture". Overall the picture quality was still considered inferior to the best kinescope recordings on film. Bing Crosby Enterprises hoped to have a commercial version available in 1954 but none came forth.

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