SNDMSG existed as a single-computer (non-host, non-network) electronic mail program from the early 1960s for time-sharing operating systems. The early versions of SNDMSG allowed users to compose a message that would be stored in a file on another user's home directory.

SNDMSG later became one component of a networked mail program written for the TENEX

TENEX

TENEX may refer to:* The TENEX operating system , an operating system for the DEC PDP-10* Tekhsnabexport, a Russian company specializing in export of nuclear materials...

 operating system by Ray Tomlinson

Ray Tomlinson

Raymond Samuel Tomlinson is a programmer who implemented an email system in 1971 on the ARPANET. Email had been previously sent on other networks such as AUTODIN and PLATO. It was the first system able to send mail between users on different hosts connected to the ARPAnet...

 (in 1971). The other component was READMAIL.