The purpose of a sway bar, anti-roll bar or stabilizer bar is to add stability to a car while maneuvering corners and bumpy terrain. The bar raises or lowers one side of the car to match the other side, which helps the car undertake corners and prevents rolling.
Different types of sway bars include adjustable sway bars and MacPherson struts. Some drawbacks of the sway bar is that bumps are felt from both sides of the car, and cracked pavement can cause a back-and-forth movement in the vehicle. The sway bar was first patented in 1919 by Stephen Coleman, but the device was not commonly used until the 1950s.