At MIT Fernando Corbato develops the "Compatible Time Sharing System," Precursor of Word Processing and Email

In 1961 Fernando J. Corbató and team at MIT developed one of the first time-sharing operating systems, CTSS (Compatible Time-Sharing System) running on an IBM 7094 mainframe.

CTSS had one of the first computerized text formatting utilities, called RUNOFF, the precursor of word processing, and one of the first inter-user messaging implementations, presaging instant messaging and electronic mail.