Gaming has evolved in countless ways over the past few years, bridging the gap between platforms in a way that nobody could have foreseen at the dawn of the last console generation. With things like Play Anywhere coming out of the woodwork and encouraging Xbox users to play more games on PC (and vice versa) the need is now greater than ever for people to learn how to use an Xbox controller on a Windows 10 PC. Thankfully, the process is extremely simple, and with a few extra tips under your belt you can get just about any PC game functioning smoothly for you.
If you're working with a game that already natively has support for controllers, then you really don't need to know much. It's as simple as taking a micro-USB cable and plugging your controller into your desktop. Chances are you already have one of these lying around the house, but they can be bought pretty much anywhere hardware is sold for an extremely low price. Once you've plugged in, that's it - no further steps, no complications, no strings attached. Since Windows 10 was made with the Xbox controller in mind as the intended gamepad, the whole experience is totally plug-and-play.
If you don't feel like constraining yourself to a cord and would rather have a more authentic Xbox experience with your desktop, you can also consider picking up the Xbox Wireless Adapter. The peripheral is a simple USB stick that can plug right into your desktop, making it so your controller picks up device as if it were an Xbox One. The peripheral costs $25 USD if you decide you want it brand new, so it's a pricier - albeit more elegant - option for gamers who want to make the most out of their PC gaming experience.
If your game doesn't have support for controllers, then you're mostly out of luck. Programs like AutoHotkey can let you use a controller to interface with your computer (and by extension, games) but you'll find that, generally speaking, the end result tends to be a lot less enjoyable than it would be with a keyboard and mouse. That said, individual communities for games have been known to set up ways of creating controller compatibility, so you should go lurking around forums or your game's subreddit before you give up hope.
Many games just aren't meant for controller support - most shooters tend to be better with keyboard and mouse from a competitive standpoint, and a lot of MMO's can feel a lot better with their traditional keyboard and mouse format. A lot of PC games, however, feel amazing with a controller. If you've never taken the time to try out a controller with your PC games, you should really give it a shot. While it's not often the most competitively viable thing to do for hardcore, hyper-competitive gamers, switching to an Xbox controller can make a game you've been playing for years feel fresh and new.