SquirrelMail is a standards-based webmail package written in PHP. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.0 (with no JavaScript required) for maximum compatibility across browsers. In simple terms, SquirrelMail aims to make receiving mail on-the-go as easy as possible. The interface within SquirrelMail provides for great usability across all platforms such as mobile browsers and older web browsers.