It’s Open Broadcaster Software, it’s open source, available for Windows/Mac/Linux. A lot of Streamers use it to stream as well.
For the most part, it records well, and I like the fact that you can choose if or not it records your mouse cursor, and also if you want other things on your screen recorded. Right now if I am playing someone messages me, I will see the message pop up, but it won’t show up in the video. Of course the “ding” sound shows up in the video, but that hardly matters.