Every track you play will tell your Last.fm profile something about what you like. It can connect you to other people who like what you like - and recommend songs from their music collections and yours too.
…and as you use Last.fm, you make it better for you and everyone else.

When you recommend some music to a friend, or you tag it, or you write about it - even just listening to it - you shift the song’s importance on the site. It’ll be recommended to different people, because you’ve listened to it. It’ll move up our music charts and maybe more people will hear it because you thought it was good.