The term Webmail (or Web-based e-mail) is used to describe two things. One use of the word is to describe a Webmail client: an email client implemented as a web application accessed via a web browser. This article focuses in this use of the term. The other use of the word is to describe an email service offered through a web site (a webmail provider) such as Hotmail, Yahoo! Mail, Gmail, and AOL Mail;. Practically every webmail provider offers email access using a webmail client, and many of them 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 wherever there's a web browser. Its main disadvantage is the need to be connected to the internet while using it (Gmail offers offline use of its webmail client through the installation of Gears.).
In the early days of the web, in 1994 and 1995, several people were working on enabling email to be accessed on a web browser. In Europe, Soren Vejrum and Luca Manunza released their "WWW Mail" and "WebMail" applications, whereas in the United States, Matt Mankins wrote "Webex". Each of these early applications were perl scripts which included the full source code available for download.
Also in 1994, Bill Fitler, while at Lotus cc:Mail in Mountain View, California, began working on an implementation of web-based email as a CGI program written in C on Windows NT, and demonstrated it publicly at Lotusphere in January 1995.
Soren Vejrum's "WWW Mail" was written when he was studying and working at the Copenhagen Business School in Denmark, and was released on February 28, 1995. Luca Manuza's WebMail was written while he was working at CRS4, in Sardinia, with the first source release on March 30, 1995. In the United States, Matt Mankins, under the supervision of Dr. Burt Rosenberg at the University of Miami  released his "Webex" application source code in a post to comp.mail.misc on August 8, 1995, although it had been use as the primary e-mail application at the School of Architecture where Mankins worked for some months prior.
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