Hotmail.com vs Outlook.com:
Microsoft bought Hotmail in 1996. However, the email service went through several names, including MSN (Microsoft Network), Hotmail, and Windows Live Hotmail.
Microsoft release the last version of Hotmail in 2011. However, Outlook.com replaced Hotmail in 2013. At that time, The users of the Hotmail were given the choice to keep their Hotmail email addresses and to use them with the Outlook.com domain. You can still get an email address with @hotmail extension.