The client is available for free from the following location, and is a simple drag-and-drop installation to your Applications folder: Many of these games are run using Wine-like compatibility layer for OS X, which has been seen in applications like Codeweaver's 'Crossover' and 'Crossover Games' packages, which offer very high performance solutions to porting Windows games to OS X and other Unix-like operating systems. Valve offers over a thousand games through Steam, and for OS X the debut will see Left 4 Dead, Left 4 Dead 2, Team Fortress 2, Counter-Strike: Source, Portal, and the whole Half-Life series available. In addition, the program offers networking options for locating and joining online game servers, chatting, and providing in-game communication enhancements.
Similar to the iTunes store, Steam is a single program through which you can purchase, download, and manage games for your computer. For the gamers out there, Valve software's 'Steam' gaming client package is available.