Hotmail By Outlook.com

Outlook.com is a web-based suite of email, contacts, tasks, and calendaring services from Microsoft. One of the world's first webmail services, it was founded in 1996 as Hotmail (stylized as HoTMaiL) by Sabeer Bhatia and Jack Smith in Mountain View, California, and headquartered in Sunnyvale. Hotmail was acquired by Microsoft in 1997 for an estimated $400 million and launched as MSN Hotmail, later re-branded to Windows Live Hotmail as part of the Windows Live suite of products.

Microsoft released the final version of Hotmail in October 2011, available in 36 languages. It was replaced by Outlook.com in 2013. By 2014, the service had 400 million active users. Outlook.com follows Microsoft's Metro design language, closely mimicking the interface of Microsoft Outlook. It also features unlimited storage, a calendar, contacts management, Ajax, and close integration with OneDrive, Office Online and Skype. In May 2015 it was announced that a preview of the new Outlook.com will move it to the Office 365 infrastructure. Microsoft concluded its preview stage in February 2016, when it began to roll out the new version to users' accounts, beginning with North America.

Hotmail was sold to Microsoft in December 1997 for a reported $400 million, and it joined the MSN group of services. Hotmail quickly gained in popularity as it was localized for different markets around the globe, and became the world's largest webmail service with more than 30 million active members reported by February 1999. Hotmail originally ran on a mixture of FreeBSD and Solaris operating systems. A project was started to move Hotmail to Windows 2000. In June 2001, Microsoft claimed this had been completed; a few days later they retracted and admitted that the DNS functions of the Hotmail system were still reliant on FreeBSD. In 2002 Hotmail still ran its infrastructure on UNIX servers, with only the front-end converted to Windows 2000. Later development saw the service tied with Microsoft's web authentication scheme, Microsoft Passport (now Microsoft account), and integration with Microsoft's instant messaging and social networking programs, MSN Messenger and MSN Spaces (now Windows Live Messenger and Windows Live Spaces, respectively).

In 1999, hackers revealed a security flaw in Hotmail that permitted anybody to log in to any Hotmail account using the password 'eh'. At the time it was called "the most widespread security incident in the history of the Web". In 2001, the Hotmail service was compromised again by computer hackers who discovered that anyone could log in to their Hotmail account and then pull messages from any other Hotmail account by crafting a URL with the second account's username and a valid message number. It was such a simple attack that by the time the patch was made, dozens of newspapers and hundreds of web sites published exact descriptions allowing tens of thousands of hackers to run rampant across Hotmail. The exploitable vulnerability exposed millions of accounts to tampering between August 7, 2001 and August 31, 2001.

Microsoft's new email system was announced on November 1, 2005, under the codename "Kahuna", and a beta version was released to a few thousand testers. Other webmail enthusiasts also wanting to try the beta version could request an invitation granting access. The new service was built from scratch and emphasized three main concepts of being "faster, simpler, and safer". New versions of the beta service were rolled out over the development period, and by the end of 2006 the number of beta testers had reached the millions. The Hotmail brand was planned to be phased-out when Microsoft announced that the new mail system would be called Windows Live Mail, but the developers soon backtracked after beta-testers were confused with the name change and preferred the already well-known Hotmail name, and decided on Windows Live Hotmail. After a period of beta testing, it was officially released to new and existing users in the Netherlands on November 9, 2006, as a pilot market. Development of the beta was finished in April 2007, Windows Live Hotmail was released to new registrations on May 7, 2007, as the 260 million MSN Hotmail accounts worldwide gained access to the new system. The old MSN Hotmail interface was accessible only by users who registered before the Windows Live Hotmail release date and had not chosen to update to the new service. The roll-out to all existing users was completed in October 2007.