It's National Tire Safety Week, and that means it's a good time for drivers to focus on perhaps the four most important aspects of their vehicle. Getting stuck with a flat tire is typically thought of as more of a inconvenience than a danger, but those who have experienced a flat tire while driving on a highway know it's nothing to be messed around with - losing control for even a second can lead to an accident.

According to Pep Boys, underinflated tires lead to 660 fatalities and 33,000 injuries in the U.S. each year. This is a truly tragic statistic, as checking your tire pressure and inflating your tires is really quite simple to do. Yet the Rubber Manufacturers Association found in a study that 85 percent of motorists don't know how to do it.

There's a simple valve on the side of the tire that needs to be unscrewed. Simply pull your car up to an air pump and fill it like you would a tank of gas. The only tricky part is you have to monitor your progress with a pressure gauge, but nearly all gas stations have one.

Even if you're not convinced by the safety considerations, think about the economics of it: cars with properly inflated tires get 3.3 percent better fuel economy on average.