If you have a system with a working Postfix install (in this case, it’s likely that it was configured during install) and you want to send an email from the command line, you can do so with the following:
mail -s “subject” [email protected]
email content goes here
.
Type in the first line, hit enter, type out your content, hit enter, type a single fullstop, hit enter, and your email is sent!