Most cabinet door builds were calling for something called mortise and tenon joints for the frame portion and some others were also calling for a dado. I had to look those up. Mortise and tenon joints are a form of connecting two boards that has been around for thousands of years. It is basically like plugging one piece into another using specific holes you have created. A dado is a small groove cut into a board for another board to rest on.
Either way, I did not have the tools for either of those things. Maybe one day I will become more professional, but this was not the day. So, the solution? Pocket holes, of course!