What is Sendmail ?

About

Sendmail was the first well-known SMTP server.

The server has the following components:

• a mail transfer agent (MTA) to send mail to the outside world
• a mail deliver agent (MDA) to receive email from the outside world
• a command line (MUA) to send a message

Command line interface as reference

The command line client sendmail has become a de facto interface because it's used by client to send email as an interface (mailx, …)

Almost all MTAs provide a sendmail interface making it the default implementation.

For instance, postfix postfix is a Sendmail-compatible MTA and therefore provides a sendmail command in its installation.

Documentation / Reference

• http://www.elandsys.com/resources/sendmail/