MSN Messenger is quite a basic piece of software but has some really cool features, I was first introduced to it around 6/7 years ago now when it became the new hype at school, if you wern't on msn at the time then you were part of the outcast's!

Once signed up with Hotmail you simply download the application and login with your e-mail address, you can then add friends with their e-mail address or by name or telephone number if i remember correctly.
It is very user friendly as you can organise your friends in to lists, see easily when people are on or offline, start a live chat instantly by just clicking on a friend, once in an active conversation you can exchange webcams with audio, send small audio clips, send smiley emotions, and then other extra's like winks and nudge which you can use to grab the other persons attention!

There is also a large range of games available from Microsoft which can be played live between you and your friend, whilst you chat at the same time.

I think MSN has gradually lost its popularity since social network sites like Facebook and Twitter became more popular, however I do think there are valuable features within MSN which are lacked with the competitor platforms.