A helmet is a hard protective covering worn on your head to prevent injuries. Helmets are designed to absorb the force of impacts, protecting your skull and brain from serious harm. When you ride a bike, skateboard, or scooter, a helmet can help protect you from head injuries.

Different activities require different types of helmets. A bicycle helmet has ventilation holes to keep you cool, while a football helmet includes a face mask and thick padding to protect against tackles. Construction workers wear hard hats, a type of helmet that shields them from falling objects. Firefighters wear helmets that can withstand extreme heat, and astronauts wear helmets as part of their spacesuits to survive in the vacuum of space.

Throughout history, soldiers wore metal helmets in battle, from ancient Greek warriors with bronze helmets featuring distinctive crests to medieval knights in full armor. Modern military helmets use advanced materials like Kevlar.