First aid is emergency care or treatment provided to an injured or ill person until full medical treatment is available. It involves assessing the situation, protecting oneself from danger, ensuring the scene is safe, and providing initial care such as stopping bleeding, treating for shock, or applying splints. The key aims of first aid are to preserve life, prevent further harm, and promote recovery. Effective first aid requires training to learn skills like clearing airways, rescue breathing, controlling bleeding, and treating injuries.