Not many exercises can activate 200 muscles at one time and help you increase strength, burn fat and build muscle at the same time. The squat is the one exercise that can.
If you’re interested in the science of the squat then I strongly suggest you take a look at The Science of Squatting. This is a presentation given at a recent conference.
As well as going into significant detail about the muscles, joints and forces that are at play when performing the “king of exercises”, the presentation also delves into technique and the benefits and contraindications of performing the squat in particularly ways.
If you’re into training heavy, then this is well worth a look.