Car seats are an important part of keeping children safe while you’re driving. But the array of seat types and installation requirements can make for major confusion. The car seat you need depends on your child's age, size and weight. Here's what you need to know to make sure you have the right type of car seat in the right position in your car, truck or van. From Birth to Age 2 Newborns, infants, and children under the age of 2 must ride in a rear-facing car seat in the back seat of your vehicle. When accidents occur, children are much less likely to be badly hurt when riding in a rear-facing seat. There are different types of rear-facing car seats: Infant-only car seats. These often double as carriers so babies can stay in them when being placed in or taken out of a vehicle. Infant car seats use a five-point harness that attaches at the baby’s shoulders and hips, and between the legs. The five-point harness is designed to secure the child's upper body, head and neck. You’ll need to follow the height and weight limits for the type of car seat you buy. Each car seat model has its own limit, which is marked on the box the car seat comes in as well as the car seat itself. Convertible car seats. Once your child reaches the maximum allowed weight and height for your model of infant car seat, he or she will graduate to a “convertible” car seat. Like infant car seats, convertible car seats have a five-point harness. But unlike infant car seats, convertible car seats are not portable. You install them in a rear-facing position in your car’s back seat and leave them in your car. Different convertible car seat models are made to protect children of different height and weight ranges, such as up to 40 pounds and 40 inches. 3-in-1 car seats. 3-in-1 car seats are convertible car seats that can become booster seats later on. 3-in-1 car seats are often bigger than convertible seats. They might not fit in all makes and models of cars in the rear-facing position. From 2 to 5 Years Old When children turn 2 years old, they can face forward in their convertible or 3-in-1 car seat. They still need to ride in the back seat. Children should ride in convertible or 3-in-1 car seat until they are 5 years old or reach the maximum height and weight for their particular seat, which is usually about 40 pounds. Watch for these signs children have outgrown a forward-facing convertible or 3-in-1 car seat: Their shoulders are above the harness slots. Their ears are level with the top of the seat. 5 Years of Age and Up Once children are about 5 years old and have reached the height and weight limits of their convertible or 3-in-1 car seats, they can move into a belt-positioning booster seat. Booster seats do not come with a harness. Instead, they work with the lap and shoulder seat belts that come with your car. Seat belts were designed for adult-sized bodies. Booster seats work by raising children up high enough so the lap and shoulder belts fit them properly. Belt-positioning booster seats are available in two models: Backless. These booster seats are used only in vehicles with a high seat back that supports the child’s head. The seat back must reach the top of the child’s ears. High-back. These boosters are for vehicles with a low seat back that doesn’t provide enough support to the child’s head. Children should continue to ride in booster seats until they’re able to safely use the car's lap and shoulder seat belt. They're ready to use a seat belt without a booster seat when: The lap belt crosses their upper thighs, not the stomach. The shoulder strap crosses the chest, not the face or neck. They can sit back in the seat comfortably, with their knees bent over the edge of the seat without slouching. Most often, children need to be at least 4 feet 9 inches tall and 8 to 12 years old to no longer need a booster seat. Even after they stop needing a booster seat, children should continue to ride in the back seat until they are 13 years old. There may be exceptions to this age if your child is small. Passenger airbags also come into play. Visit your local fire station for more information on when to allow your older child to ride in the front.