From Valve:Steam provides over 2,000 games available to purchase, download, and play from any computer. Check out the new releases, indie hits, casual favorites and everything in between. Find someone to play with, meet up with friends, connect with groups of similar interests, and host and join chats, matches, and tournaments. See when your friends are online or playing games and easily join the same games together. Chat with your buddies, or use your microphone to communicate in any game. On Steam, your games stay up-to-date by themselves with automatic game updates.