I couldn't resist answering to these questions. Originally googleing for some information about pre-load for GTA IV on Steam, but got kind of provoked you guys don't understand the sole idea of Steam.Steam is an application for distribution of games. These games are locked to your account. If a friend of yours log in to Steam with his account, he can't play all the games you've got, unless he's bought them on his account too.If you are at someone elses house and wanna play, lets say, Left 4 Dead, but they don't have it installed, you login to your account, download it, and play. When you're done, log off, and they cannot play it unless they buy it too. One account cannot login at more than one computer at a time.Easy as that.