Types of car seats
Infants and toddlers: rear facing only or rear facing convertible. All infants and toddlers should ride in a rear facing seat until they are at least 2 years old or reach the highest weight or height allowed by their car seat manufacturer
Toddlers and preschoolers: Convertible or forward facing with harness. Children who have outgrown the rear facing weight or height limit for their convertible seat should use a foward facing seat with a harness for as long as possible, up to the highest weight or height allowed by their car safety seat manufacturer.
School aged children: Booster seats. All children whose weight or height exceeds the forward facing limit for their car safety seat should use a belt positioning booster seat until the vehicle seat belt fits properly, typically when they have reached 4 feet 9 inches in height and are 8 through 12 years of age. All children younger than 13 should ride in the back seat.
Older children: seat belts. When children are old enough and large enough for the vehicle seat belt to fit them correctly, they should always use lap and shoulder seat belts for the best protection. All children younger than 13 years should ride in the back seat.
Car seats may be installed with either the vehicle seat belt or latch system. A latch is an attachment system for car seats. Lower anchors can be used instead of the seat belt to install the seat. The top tether improves safety provided by the seat and is important to use for all forward facing seats, even those installed using the seat belt. If you install a car seat using your seat belt, you must make sure the seat belt locks to help get a tight fit.
The safest place to ride for all children younger than13 is the back seat.
There are three types of rear facing seats available: rear facing only, convertible, and 3-in-1.
Rear facing only seats are used for infants up to 22 to 45 pounds, depending on the model. They are small, have carrying handles and sometimes are part of a stroller system. They ususlly come with a base that can be left in the car. the seat clicks into and out of the base so you don't have to install it each time.
Convertible seats can by used rear facing and later converted to forward facing for older children when they outgrow the weight limit, the length limit, or both for rear facing. They are bulkier than infant seats, however, and do ot come with carrying handkles or separate bases. Many have higher limits in rear facing weight (up to 40-50 pouonds) and height than rear facing only seats, which make them ideal for bigger babies and toddlers. They have a 5 point harness that attaches at the shoulders, hips and between the legs.
3-in-1 seats can be used rear facing, forward facing, or as a belt positioning booster. This means the seat can be used longer by your child. They are bigger insize, so it is important to check that they fit in the vehicle while rear facing. They do not have a carrying handle or separtate base, however, they may have higher limits in rear facing weight and height than rear facing only seats, which make them ideal for bigger babies and toddlers. For more information and to review the tips given here please refer to the following: https://www.healthychildren.org/English/safety-prevention/on-the-go/Pages/Car-Safety-Seats-Information-for-Families.aspx