I'm quickly going to write about what I use to record my Youtube videos. I use very basic and inexpensive equipment compared to people that do it professionally.
For playing games I have an Xbox One and the first iteration of the controller. I also use my PC and Corsair K95 Mechanical keyboard with Cherry browns supplemented with a Mad Catz MMO TE mouse or an Xbox 360 controller.
My PC is custom built. It features an i7 4770k, 16GB of DDR3 Corsair RAM, and an ASUS Maximus VII Hero motherboard. Graphics are powered by a Gigabyte G1 Gaming 970.
For recording my Xbox One I use the Xbox app on my Windows 10 PC. I then stream my Xbox to the PC and by having a Gigabit switch that both are connected to I can stream in the Xbox's native quality. I then set Shadowplay to record the desktop and it will record everything except the dropdown menu that appears for streaming which is a lifesaver. For recording PC games I also use Shadowplay. My only wish is that Shadowplay would recognize Windows store apps as fullscreen games. This works extremely well for me, however once in a while streaming my Xbox does cause a sound or graphical glitch.
To record audio during gameplay I use garageband on my Macbook Pro with a Samson Meteorite microphone. I started off using my keyboard to match the audio to video but then used the 1-2-3 method after trying to match 2 videos. To record a voiceover I use the iMovie built in feature after editing my video in iMovie. However I have acquired Autodesk Smoke and hope to be using that in the coming days once I learn the advanced UI.
I hope this gives a little insight into my setup and how I work. It's getting easier and cheaper to get into videos which is one reason I've been into it more recently. I hope to improve my setup as well as video quality as time goes on.