> When the Computing Sciences Research Center wanted to use Unix on a machine larger than the PDP-7, while another department needed a word processor, Thompson and Ritchie added text processing capabilities to Unix and received funding for a PDP-11/20.[5] For the first time in 1970, the Unix operating system was officially named and ran on the PDP-11/20. A text-formatting program called roff and a text editor were added. All three were written in PDP-11/20 assembly language. Bell Labs used this initial text-processing system, consisting of Unix, roff, and the editor, for text processing of patent applications. Roff soon evolved into troff, the first electronic publishing program with full typesetting capability.
