As modern armies became mechanized, they needed to find ways to transport material across uneven terrain. One solution, developed by several countries during World War II, was a truck with wheels in the front and tracks in the back to help drive it over rough country—the “half-track.” In the US, 43,000 halftracks were produced by three primary manufacturers, the largest being the White Motor Company, the original designer, with a total of 15,414 accepted by the War Department. The other manufacturers, Autocar and Diamond T, built 12,168 and 12,421, respectively.