The Wiki gives an explaination to what happens in game development. It explains High concept, Design, production, programming, level design, the milestones of Pre- / Alpha, Beta, and gold master, the art and audio production, and a lot more.
There's a tutorial by GriffPatch that covers all the things you need to do when making games. He covers Gravity, Movement, Hitboxes, Animation, momentum, backgrounds, and platforms. He made it to teach new "scratchers" what to do if they wanna make their own games. (yes this project was basically useless in points.)