Windows is pretty much the go-to operating system for most people. And while most people use it because it already came with their laptop or desktop purchase, it’s also quite popular for those that like to build their own PCs. Sure, you could go with an alternative like Linux, but for most, Windows is going to be the only option. The only problem is that if you’re trying to buy a copy of Windows, it can cost quite a bit, with prices starting at $139.