Knowing what graphics card/GPU (that's graphics processing unit) you have makes it much easier to know what games you can play.
On Windows, you can check your graphics card by opening the Task Manager and selecting the Performance tab. Scroll down until you find GPU 0 to see the name of your graphics card.
On a Mac, you can find out your graphics card by selecting the Apple icon, then About this Mac.
It's important to know your graphics card before upgrading or buying a new one.