If your knees make this awful din whenever you squat down or crouch, and again as you are coming back up to standing position; rather like a packet of rice crisps, like a series of cracking or popping sounds, then you have probably wondered what on earth the matter with you is!
You are an otherwise healthy and fairly active person and you have reason to be worried about your knees[Knee injury] as you think of yourself as young and vital, not old and creaky!
The rule of thumb here with creaking or snapping joints, particularly the knees of ankles, is that they are generally no reason to worry unless this creaking and snapping is accompanied by pain.
If there is pain, then the noise and pain should be evaluated and diagnosed for any underlying problem. And this is common in very young people, some of whom may be in their early 20s or even teens.
When there is pain accompanying the popping or creaking sound of the knees, this could be the warning that your knees need help, otherwise it is just something that may be a little disconcerting, but simply something that you need to live with!