A booster seat is a special seat designed for children who have outgrown their car seats but are still too small to use a regular seat belt safely. It raises the child up so that the seat belt fits properly across their body, helping to protect them in case of an accident. Booster seats are typically used for kids aged 4 to 12 years, depending on their size and weight. Using a booster seat is important for safety. It ensures that the lap belt sits low across the child's hips and the shoulder belt crosses their chest, reducing the risk of injury. Parents should always check the manufacturer's guidelines to choose the right booster seat for their child's age and size.