To send and receive e-mails that we are accustomed to Web-based services such as Gmail, Yahoo etc or desktop-based email clients. However, on Linux, you can easily send / receive emails from the command line as well. This is useful in situations such as sending mail from shell scripts or other type of program.
This tutorial explains how to use the mail command on linux for sending and receiving mails.
Depending on your linux distribution, you may need to install additional packages like mailutils to get the mail command to work.