It's important to have the proper air pressure in your tires, as underinflation may lead to tire failure. The right amount of air for your tires is specified by the vehicle manufacturer and is shown on the vehicle door edge, door post, glove box door or fuel door. It is also listed in the owner's manual.
Misalignment of wheels in the front or rear can cause uneven and rapid treadwear and should be corrected by a tire dealer. Front-wheel-drive vehicles, and those with independent rear suspension, require alignment of all four wheels. Have your alignment checked periodically as specified by the vehicles' owners manual or whenever you have an indication of trouble such as "pulling" or vibration.
Also have your tire balance checked periodically. An unbalanced tire and wheel assembly may result in irregular wear.