MSN
MSN (the Microsoft Network), is a web portal (a website used to enter the Internet).
Web portal
The web portal launched on August 24 1995 by Microsoft. The site was launched at around the same time as Windows 95. Through MSN, people can create an e-mail account using MSN Hotmail, a blog using MSN Spaces, a group using MSN Groups and plenty more. It is now the #2 visited site in the world behind Yahoo!. Many people have come across this site in one way or another because it is the default main page of Internet Explorer.
MSN Messenger
MSN is also the name for MSN Messenger (now called Windows Live Messenger). It is an instant messenger, which allows people to communicate through conversations over an internet connection. As well as conversations using text, this program also allows voice and video conversations. You can even use small emoticons to express what you are trying to say. Messages are sent and received very quickly from around the globe. Its current messenger client is Windows Live Messenger.
MSN Hotmail
Hotmail is a free email service from MSN. It started in 1995. It was bought by Microsoft in 1997. Microsoft Hotmail accounts are used to log in to MSN Messenger.