Editing Typesetting (section)

===Troff and successors===
{{Main|Troff}}
During the mid-1970s, [[Joe Ossanna]], working at [[Bell Laboratories]], wrote the troff typesetting program to drive a Wang C/A/T [[phototypesetter]] owned by the Labs; it was later enhanced by [[Brian Kernighan]] to support output to different equipment, such as [[laser printer]]s. While its use has fallen off, it is still included with a number of [[Unix]] and [[Unix-like]] systems, and has been used to typeset a number of high-profile technical and computer books. Some versions, as well as a [[GNU]] work-alike called [[groff (software)|groff]], are now [[open source]].