E (PC-DOS)
E is the text editor which was made part of PC DOS with version 6.1 in June 1993, and later with version 7 and PC DOS 2000. In version 6.1, IBM dropped QBASIC, which, in its edit mode, was also the system text editor. It was necessary to provide some sort of editor, so IBM chose to adapt and substantially extend its OS/2 System Editor (1986), a minimally functional member of the E family of Editors. The DOS version is extended with a wide array of functions that are usually associated with more functional versions of the E editor family (see below). In version 7, IBM added the REXX language to DOS, restoring programmability to the basic box. IBM also provided E with OS/2.