The IBM MT/ST (Magnetic Tape/Selectric Typewriter) is a model of the IBM Selectric typewriter integrated with magnetic tape recording and playback facilities and built into its own small desk. It was released by IBM in 1964. It recorded text typed on magnetic tape, 25 kilobytes per cassette tape, and allowed editing and re-recording during playback. It was the first system marketed as a word processor. Versions with two tape drives enabled features such as mail merge.
In 1967, Jim Henson was contracted by IBM to produce and direct a short film on the MT/ST; the film, called Paperwork Explosion, was scored by Raymond Scott.
The MT/ST became obsolete in the 1970s in favor of floppy disk-based systems.