What is the domain name used by Microsoft's Outlook.com email service?

The domain name used by Microsoft’s Outlook.com email service is outlook.com. It appears in addresses such as [email protected] and identifies the modern consumer webmail brand that replaced Hotmail’s public-facing identity.

The service began as Hotmail, founded by Sabeer Bhatia and Jack Smith and commercially launched on July 4, 1996. Microsoft acquired it in 1997 and later renamed it MSN Hotmail, then Windows Live Hotmail. Microsoft introduced Outlook.com in 2012 and completed the transition from Hotmail in 2013.

Legacy addresses remain important to the story. Microsoft continues to support many existing @hotmail.com addresses, and older accounts may also use @live.com or other historical Microsoft domains. Those are valid legacy identities, but they are not the canonical modern domain name asked for here. Outlook.com is also distinct from Microsoft Outlook, the desktop and mobile email application. The web service can be accessed through a browser and can also be connected to email clients using protocols such as IMAP and POP.