Quality control is something that's a key part of almost every industry and every job. You probably engage in your own form of quality control several times a day. If you proofread your e-mail before you send it, that's a form of quality control. Even this article is the result of a type of quality control system. The editor who publishes it onto the HowStuffWorks.com Web site will check the published version for things like spacing issues, image size and position and broken links.
It's a similar process in auto manufacturing. But you can't put something through quality control until it's actually built. So, in automobile manufacturing, quality control starts with the prototype of a car. From there, the prototype is put through its paces.
Engineers have designed several tests to determine how well a car will stand up to real-world (and extreme) use. For instance, they drive the prototype car over specially designed surfaces to test the smoothness of the ride and the durability of the suspension. They also expose the cars to extreme heat and cold weather to test how the various mechanical components will work in all types of weather. They even fill a car with smoke and then check all the window and door seals to insure it's airtight.
One of the most well-known quality-control tests is the crash test. While most people are familiar with government and insurance industry crash tests, car makers also run their own tests to make sure its products and safety systems will work as they were designed to and protect the vehicle's occupants.
Up next, learn about some of the advances made in automotive quality control.