Below is translated with AI so there might be some strange wordings... :)
Squats is the English word for the old classic exercise squat . Now, however, it's not quite that simple due to the fact that the variety of squats, especially in crossfit has more or less exploded.
The squat is an important and fundamental exercise as it strengthens the muscles in many areas at the same time: hips, butt, thighs, stomach and back. In addition, this "squatting movement" also trains balance, mobility and coordination very effectively.
Squat/Squat is a so-called multi-joint exercise, which primarily strengthens the lower part of the body and is also included as a part of powerlifting (the sport itself where you lift scrap). The focus of the exercise is on the quadriceps, gluteus maximus and hamstring muscles (i.e. thighs, buttocks and back thighs), but the calves and lower back are also activated.
The movement is classically done so that from an upright position with a barbell on your shoulders, you squat down and then stand up again. Correct technique is important, otherwise there is a risk of injury. The back must be kept neutral/straight so as not to overload the lower back - it is easy to "curve" the back the further down you go. The knee should point towards the direction of the foot through the lift. Belt can be used to provide support. When the lift takes place with the barbell on the shoulders, this is called a "back squat". Here, Daniel Richter at the strength lab shows the technique in a nice video .
In crossfit, the front squat is instead more common and this means that instead of having the barbell on the shoulders, you have it on the front of the body and let it rest on the collarbones and the front part of the deltoid muscle (i.e. the shoulder muscles). If you look into Crossfit's own channel, you can see in detail here how to do it - stand shoulder-width apart, hands just outside the shoulders, light grip/finger grip on the bar, high elbows, in the bend the hips should be lower than the knees, keep the form in the back and the heels should be in the ground.
In addition to back squat and front squat, you can also do squats with a free weight in your hands (such as a kettlebell ), and then the exercise is called the Goblet Squat . Last but not least, you can do squats advantageously without weights at all and then the exercise is called Air Squat. There are also additional variations on the squat in several different forms, but the principle is the same - squat down and back up.
How deep should you go then? In sports where you compete in squats, the requirement is that the "fold" that forms at the hip, between the stomach and the thigh, must be lower than the highest point of the knee. As a guideline, you can think that the thigh should be parallel to the ground. However, it has been shown that going deep is very beneficial for muscle growth and, moreover, you become strong by training from the "bottom position" - Dare to go deep, but think about a neutral back. Read this nice article from Sport Science, which writes good stuff about what works in training.