A sidecar is a one-wheeled attachment that is connected to the side of a motorcycle. It allows an additional passenger or cargo to be carried alongside the bike, enhancing its utility. Sidecars can be found in various designs, often featuring a seat, a wheel, and a frame that connects to the motorcycle. Originally popular in the early 20th century, sidecars were used for both transportation and military purposes. They provide stability and balance, making it easier to ride with a passenger. Many motorcycle enthusiasts enjoy customizing their sidecars for unique looks and improved performance, often incorporating elements from vintage motorcycles or modern designs.