An operating system is the essential software that's needed to run your computer's suite of software. Everything from video ...

What Is an Operating System? An operating system (OS) is the fundamental software that acts as the brain of your computer. It's the master program that orchestrates all the computer's operations, ...

If you've never installed an OS before, it's remarkably easy. If you have, I'd still suggest reading through this guide to make sure you've got it all down. Installing Windows on a custom machine can ...

A beta version of Valve's gaming operating system is now available for download. Here's how you can transform your current computer into a Steam Machine. Dan Graziano is an associate editor for CNET.