How many typewriters are you likely to find in an office today? Probably none, but in the mid-1960s they were plentiful. That was when IBM coined the term "word processing" to market their Magnetic Tape Selectric Typewriter, also known as the MTST. It was very different from other typewriters because it recorded words on magnetic tape and printed them on paper at the same time. Each tape could store many documents, making it possible to retrieve any of them for later printing, or for generating multiple copies of the same document. This was the first device to allow semi-automatic production of personalized letters: after the user typed the names and addresses, the machine took over and completed the task.

The MTST underwent many transformations, and in 1974 it used internal storage along with external storage on magnetic tapes or cards. However, fast typists could...