Just about every game requires some form of installation. However, some require the disc to be inserted to play while others copy everything to your hard drive, and yet others give you the choice. What it comes down to is it's extremely rare when you can simply insert the disc on any computer and start playing like you can on a console, but how much installation is required depends on the game.
John
I feel stupid asking this question but when you play games off a computer like a mac, can u play it off the disc or do you have to install it on your hard drive?

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