We wear helmets when riding a bike or playing sports primarily for safety reasons. Helmets are designed to protect the head in the event of a fall or collision. Here are some of the key reasons why helmets are important:

1. Head Injuries: The skull and brain are vulnerable to serious injury in an accident or impact. Helmets help absorb and distribute the force of a blow to the head, reducing the risk of traumatic brain injuries, skull fractures, and other potentially life-threatening head trauma.

2. Increased Survival Rates: Studies have shown that wearing a helmet can reduce the risk of death from a bicycle accident by around 60%. Helmets have been proven to significantly improve the chances of surviving a serious head impact.

3. Legal Requirements: In many regions, it is legally required to wear a helmet when riding a bike, especially for children and teenagers. This law helps promote helmet use and improve overall safety.

4. Role Model Behavior: When adults and athletes wear helmets, it sets a good example and encourages others, especially children, to do the same. This can help normalize helmet usage and make it a standard safety practice.

5. Sport-Specific Protection: Certain sports, like cycling, hockey, and climbing, have specialized helmets designed to protect against the specific types of impacts and falls common in those activities.

Overall, helmets provide an important safeguard against head injuries and can be a simple but effective way to dramatically improve safety and save lives when engaging in activities with a risk of falls or collisions.