It makes it selling video games. Used video games, especially. But if you've ever wanted to break that question down a little more, and see where it makes its money both in the US and overseas, here's your chance.
Gamasutra's Matt Matthews has broken down the multinational retailer's latest fiscal year results and translated them into a language we can all understand: one of charts and pretty colours.
While the chain's share of the US market is held in check by stores like Best Buy and Wal-Mart, in Europe sales are through the roof, with non-American stores now providing a serious chunk of the retailer's overall income.
So next time you complain about pre-owned game prices, Americans, remember: you're not alone!
In-Depth: Inside The Business Of GameStop, Part Two [Gamasutra]