Game Bar is a Windows 10 included overlay for gaming that allows for taking of screenshots, recording as well as broadcasting of video games. It is also the service through which you can enable “Game Mode”, which is a group of settings designed for a better gaming experience.
The Game Bar is accessed through a downloadable Xbox app or through the Start Menu. It also offers a variety of shortcuts, and the first one is used for opening it. The combination to open Game Bar is holding down the Windows key and pressing G.
To DVR record using the Game Bar open the game and the open it using the shortcut fore mentioned. That will open the Game Bar which will disappear after a bit and be replaced by a smaller bar with a couple buttons, allowing stopping recording, enable/disable the microphone or hide to bar.
The shortcuts for those functions are as follows.
Press the Windows logo key along with Alt and G to record the last 30 seconds of gameplay. You can change the length of time recorded in the Game bar settings.
The start and stop recording shortcut is Windows key along with Alt and R, while the timer can be hidden by pressing T with the combination instead of R.
For the microphone, you will have to set your own shortcut through the Xbox app menu, by navigating to Game DVR and the Keyboard shortcuts options.
The Game Bar also allows for broadcasting as well as screenshots. While broadcasting is more complex and requires preparation and setup of additional software, screenshots can be done with the key combination of the Windows key, Alt and the Print Screen key.
Keep in mind, while the Game bar is meant for gaming, it can also record or take screenshots other programs, such as web browsers or what you are doing on-screen, for example to make a tutorial for someone or show a problem.