In 1961-62 people edited text files on CTSS with INPUT which let you
type card images or EDIT which let you replace whole lines. The MODIFY command was similar for replacing lines in 12-bit character set files.
TECO was invented in 1962 for the PDP-1 by Dan Murphy for editing paper tape.
In 1963 MIT Project MAC ran a "summer study" importing man computer folks to use CTSS. Art Samuel of IBM was one visitor. He contributed a "text editor" to CTSS, originally called CTEST9. It allowed for "context editing" where a user could look at lines in a file and substitute characters.
ED and TYPSET in 1964 were a CTSS context editors that were modal:
users started the editor and switched from input mode to edit mode by typing a line of just a period.
In 1961-62 people edited text files on CTSS with INPUT which let you type card images or EDIT which let you replace whole lines. The MODIFY command was similar for replacing lines in 12-bit character set files. TECO was invented in 1962 for the PDP-1 by Dan Murphy for editing paper tape. In 1963 MIT Project MAC ran a "summer study" importing man computer folks to use CTSS. Art Samuel of IBM was one visitor. He contributed a "text editor" to CTSS, originally called CTEST9. It allowed for "context editing" where a user could look at lines in a file and substitute characters. ED and TYPSET in 1964 were a CTSS context editors that were modal: users started the editor and switched from input mode to edit mode by typing a line of just a period.