This is probably not a question you give a lot of thought to on a regular basis. Most people with knee problems steer away from the squat, and it’s certainly good to be cautious. But if you don’t have knee problems, the squat can be a really important exercise. The squat is basically the muscles we use to stand up and sit down. Most of us stand and sit at work, when we eat, when we go to the bathroom, and when we get in the car. It’s a pretty important exercise for daily use.
As people age it’s one of the more important exercises they can probably do to keep themselves independent.

Recently I read two articles that argued for the importance of a really deep squat. One where you start standing and lower your glutes until they almost touch the floor between your heals. This isn’t for everyone and some people need to build up to this, but the articles made an interesting case

They claimed that we are very sensitive about knees in the west. In parts of Asia and India, the low squat is a part of daily life that can make birthing and going to the bathroom an easier process. The article also discussed a “use it or lose it mentality.” It argued we should bend our knees as much as possible because they are meant to be able to bend that far. We have drifted very far from this line of thinking, but it’s interesting. And I think it makes a lot of sense keeping in mind that every body is different.

So, if you are tempted to try a low squat, use caution and build up slowly. It’s not worth hurting the knees, especially if they bother you already. But if you can already do a low squat and your knees are fine consider making it a part of your daily routine. The article I was reading suggested about 10 deep squats per day every day.