Web-based email

Webmail (or web-based email) is any email client implemented as a web application running on a web server. Examples of webmail software are Roundcube and SquirrelMail. Examples of webmail providers are AOL Mail, Gmail, Outlook.com/Hotmail.com and Yahoo! Mail. Many webmail providers also offer email access by a desktop email client using standard email protocols, while many internet service providers provide a webmail client as part of the email service included in their internet service package.

As with any web application, webmail's main advantage over the use of a desktop email client is the ability to send and receive email anywhere from a web browser. Its main disadvantage is the need to be connected to the Internet while using it. Other software tools also exist to integrate parts of webmail functionality into an OS (e.g. creating messages directly from third party applications via MAPI).

The first Web Mail implementation was developed at CERN in 1993 by Phillip Hallam-Baker as a test of the HTTP protocol stack. This led to the discovery that the specification of the POST method was faulty, requiring the introduction of the Content-Length header. The CERN-PTG daemon was released later that year but was not developed further.

In the early days of the web, in 1994 and 1995, several people were working on enabling email to be accessed via a web browser. In Europe, there were three implementations, Søren Vejrum's "WWW Mail",Luca Manunza's "WebMail", and Remy Wetzels' "WebMail", whereas in the United States, Matt Mankins wrote "Webex". Three of these early applications were perl scripts that included the full source code available for download. Remy Wetzels' version was a CGI program written in C on Unix.

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