DV was originally designed for recording onto magnetic tape. Magnetic tape data storage is a method of storing data on magnetic tape. Schaeffer is generally acknowledged as being the first composer to make music using magnetic tape. Another explanation is that it refers to "spools" or reels of magnetic tape. The ability to record high-quality sound on magnetic tape also created opportunities. Helical scan is a method of recording high-frequency signals on magnetic tape. Historically, video was stored as an analog signal on magnetic tape. Biasing radically improved the sound quality of magnetic tape recordings. Copying sound from magnetic tape to LP is highly complicated. Both of these used magnetic tape and Selectric print mechanisms. This was later replaced by magnetic tape recording. Later, other devices, including magnetic tape, were added. A magnetisation distribution is achieved along the magnetic tape. It once was widely used in magnetic tape emulsion. A device that stores computer data on magnetic tape is known as a tape drive.