What is what does it mean when a girl plays with your hair?

As an AI language model, I don't have personal beliefs and cannot speak for all girls. However, generally speaking, playing with someone's hair can be a sign of affection, comfort, or attraction. It can also indicate a desire for intimacy, or simply a way to pass time and relax. Different people may have different intentions or meanings behind playing with someone's hair, and it's important to communicate and understand each other's boundaries and expectations.