There are a few different things that can cause sock marks, or indentations, on your skin. One possibility is edema, which is the medical term for swelling. When you have edema, extra fluid builds up in your tissues and causes them to swell. This can happen all over your body, or just in certain areas like your feet or ankles. Edema can be caused by a variety of things, including pregnancy, heart failure, liver disease, and kidney problems. If you think you might have edema, it's important to see a doctor so they can determine the cause and start treatment.
Another possible cause of sock marks is simply wearing socks that are too tight. If your socks are leaving indentations on your skin, they're probably too snug and you should try switching to a looser pair. Wearing ill-fitting socks can not only leave marks on your skin but also lead to discomfort and even foot problems like blisters. So if you notice that your socks are leaving imprints on your skin, make sure to adjust accordingly!