It is a website that will check your settings and inform you if a particular game will run on your PC.
Can you run it
Procedure: the site is accessible with IE and Firefox, the only difference is that Internet Explorer will offer to install an ActiveX control (install it, it will scan your PC in search of your configuration) and Firefox will ask for the installation of a Java protocol.
You can see the minimum and optimal configurations required, and if your PC meets the minimum requirements.
However, the software is not fail proof.