Cats bite hands for various reasons, and it's usually not meant to be aggressive. One common cause is overstimulation—cats can get overwhelmed by too much petting, especially on sensitive areas like their belly or tail. Another reason is playfulness; kittens learn to hunt by biting, and they might see your hand as a toy. Sometimes, it's a form of communication, like telling you they've had enough attention. To prevent this, watch for signs of irritation (twitching tail, flattened ears) and stop petting before they react. Redirect their energy with toys instead of hands.