There is a Windows 10 video feature baked into the new game DVR.
Press WIN+G, and a small bar pops up, with a video-capture button. The first time you do this in a particular program, Windows will ask you to confirm that the program is a game, before starting Game DVR.
Hit WIN+ALT+R, and it will automatically start capturing video from the program you've got open, rather than the entire screen. It's a feature aimed at gamers who want to share in-game clips, but it works equally well for sending a how-to video tutorial on using Google.
more details there. (http://www.howtogeek.com/219947/how-to-record-pc-gameplay-with-windows-10%E2%80%99s-game-dvr-and-game-bar/)
To show you what could be done with it, i have created a video from my ObjReader64 playing an OpenGL 3D high polygon object in full screen mode.
Motorbike.mp4 (http://www.zapsolution.com/video/MOTORBIKE.mp4)
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