One of the most popular methods for providing portable access to email is through a web-based email client, commonly referred to as webmail. Typical webmail programs are email clients that run on, and are only accessible via, a web server. Their basic functionality is the same as that of an email client running on the user's personal machine. As such, they usually use either IMAP or, less commonly, POP3 protocols to fetch the user's email. This not only provides the ability to put the web server (and webmail software) on a computer without direct access to the mail storage (and makes it possible to change the back end without changing the webmail software), but also standardizes the authentication mechanism. The webmail software will simply authenticate via IMAP or POP3 rather than needing to perform user authentication itself. In some cases, webmail software can be packaged with other mail software to give it direct access to the mail storage. This is often done in the name of improved...