The Willys MB and the Ford GPW, both formally called the U.S. Army Truck, 1/4 ton, 4x4, Command Reconnaissance, commonly known as Jeep or jeep, and sometimes referred to as G503 are light, off-road capable, military utility vehicles that were manufactured during World War II (from 1941 to 1945) to help mobilize the Allied forces.
The design of the World War II jeep was the result of a long process, involving the contributions of both U.S. military officers and civilian engineers, the latter mostly tied to three companies: Bantam, Willys and Ford, and has repeatedly been called a design by committee. In fall 1941, Lt. E.P. Hogan of the U.S. Quartermaster Corps wrote: "Credit for the original design of the Army's truck 1⁄4-ton, 4x4, may not be claimed by any single individual or manufacturer.
*Sources: Wikipedia, KaiserWillys Blog, JeepFan.com, JeepCollection.com