Steam is an all-in-one type of program where you have all your games, instant messenger ( steam friends ), game store, game storage and more... all in one package. The steam windows client is owned by valve corporation an entertainment software company. You will need to download steam to play games like counter-strike:source, team fortress 2, left 4 dead and a bunch of other games that you can purchase through the steampowered website using the steam program. You can download the steam client software from
What is Steam. On the right handside click on the "Get Steam Now" button to begin downloading the program. Once downloaded and installed you can start purchasing games, chat with online buddies or join the games they are playing as long as you own the same game as them.
steam client system requirements
* Windows 2000, XP or Vista
* 64 MB RAM
* 400 Mhz processor
* 1GB HD space (recommended)
* Internet connection (broadband recommended)
What is steam about? 
Linear Mode
