Why do we have hair, please tell me why

 Why We Have Hair. The scalp also may have kept hair because it helped the body retain heat,

Explanation:

1. To keep us warm

2. To protect us from injury

3. humans have developed clothing and other means of keeping warm, the hair found on the head serves primarily as a source of heat insulation and cooling (when sweat evaporates from soaked hair) as well as protection from ultra-violet radiation exposure.