Outlook.com is a web-based suite of webmail, contacts, tasks, and calendaring services from Microsoft.

Founded in 1996 by Sabeer Bhatia and Jack Smith as Hotmail, Microsoft acquired it in 1997 for an estimated $400 million and launched it as MSN Hotmail, later rebranded to Windows Live Hotmail as part of the Windows Live suite of products. Microsoft released the final version of Hotmail in October 2011 and it was replaced by Outlook.com in 2012.

Hotmail service was founded by Sabeer Bhatia and Jack Smith, and was one of the first webmail services on the Internet along with Four11's RocketMail (later Yahoo! Mail). It was commercially launched on July 4, 1996, symbolizing "freedom" from ISP-based email and the ability to access a user's inbox from anywhere in the world.

The name "Hotmail" was chosen out of many possibilities ending in "-mail" as it included the letters HTML, the markup language used to create web pages (to emphasize this, the original type casing was "HoTMaiL"). The limit for free storage was 2 MB. Hotmail was initially backed by venture capital firm Draper Fisher Jurvetson. By December 1997, it reported more than 8.5 million subscribers.

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