Gmail is a free, advertising-supported email service provided by Google.Users may access Gmail as secure webmail,as well as via POP3 or IMAP4 protocols.Gmail was launched as an invitation-only beta release on April 1, 2004 and it became available to the general public on February 7, 2007, though still in beta status at that time. The service was upgraded from beta status on July 7, 2009, along with the rest of the Google Apps suite.With an initial storage capacity offer of 1 GB per user, Gmail significantly increased the webmail standard for free storage from the 2 to 4 MB its competitors such as Hotmail offered at that time.Individual Gmail messages, including attachments, may be up to 25 MB,which is larger than many other mail services support. Gmail has a search-oriented interface and a "conversation view" similar to an Internet forum. Gmail is noted by web developers for its pioneering use of Ajax.Gmail runs on Google GFE/2.0 on Linux.As of June 2012, it has 425 million active users worldwide.The idea for Gmail was pitched by Rajen Sheth during an interview with Google,and went on to be developed by Paul Buchheit several years before it was announced to the public. Initially the email client was available for use only by Google employees internally. Google announced Gmail to the public on April 1, 2004.IMAP support was added on October 24, 2007.Before its acquisition by Google, the gmail.com domain name was used by a free email service offered by Garfield.com, online home of the comic strip Garfield. After moving to a different domain, that service was then discontinued.As of June 22, 2005, Gmail's canonical URI changed from http://gmail.google.com/gmail/ to http://mail.google.com/mail/. As of November 2010, those who typed in the former URI were redirected to the latter.After Gmail's initial development and launch, many existing web mail services quickly increased their storage capacity.For example, Hotmail increased space for some users from 2 MB to 25 MB, with 250 MB after 30 days, and 2 GB for Hotmail Plus accounts. Yahoo! Mail went from 4 MB to 100 MB and 2 GB for Yahoo! Mail Plus accounts. Yahoo! Mail storage then increased to 250 MB and in late April 2005 to 1 GB. Yahoo! Mail announced that it would be providing "unlimited" storage to all its users in March 2007 and began providing it in May 2007.These were all seen as moves to stop existing users from switching to Gmail and to capitalize on the newly rekindled public interest in web mail services. The desire to catch up was especially noted in the case of MSN's Hotmail, which upgraded its email storage from 250 MB to the new Windows Live Hotmail which includes 5 GB of storage that grows with you (expands if necessary). In November 2006, MSN Hotmail upgraded all free accounts to 1 GB of storage.In June 2005, AOL started providing all AIM screen names with their own email accounts with 2 GB of storage.Google may terminate a Gmail account after nine months of inactivity.Other webmail services have different, often shorter, times for marking an account as inactive. Yahoo! Mail deactivates dormant accounts after four months.As well as increasing storage limits following the launch of Gmail, Yahoo! Mail and Hotmail also enhanced their email interfaces. During 2005, Yahoo! Mail and Hotmail matched Gmail's attachment size of 10 MB. Following the footsteps of Gmail, Yahoo! launched the Yahoo! Mail Beta service and Microsoft launched Windows Live Hotmail, both incorporating Ajax interfaces. Google increased the maximum attachment size to 20 MB in May 2007and to 25 MB in June 2009.