its like myspace but cleverer
you basically set up a page about yourself, what you like doing, and you can contact people as 'friends' but unlike myspace, you need to have each others permission to be added (so they are your friends) AND it links everyones site together
you can arrange events etc, and theres a live news feed which tells you what has been going on with the people on your friends lists.
we use it for arranging partys, bbq's, have some silly groups, and its usefull for finding old friends and uni/school colleagues.
you just check the news feed every now and again, and write messages on each others walls etc
www.facebook.com