ManaGeR or MGR was an early windowing system originally designed and developed for Sun computers in 1984 by Stephen A. Uhler, then at Bellcore.MGR featured overlapped, asynchronous windows and an applications interface that was both machine and network independent.Each MGR window had support for both character terminal operations as well as basic graphics operations. It was controlled by mousing pop-up menus, by keyboard interaction, and by escape sequences written on pseudo-terminals by client software.The system was presented at the USENIX Fourth Computer Graphics Workshop in 1987 as "MGR - a Window System for UNIX". The entire MGR source code was posted to the comp.sources.unix Usenet newsgroup, Volume 17, Issue 1, in January 1989.Internally, MGR was pronounced as munger referring to mung, although the users pronounced each letter.