The General Motors A platform (commonly called A-body) was an automobile platform, and was GM's original, and oldest, platform used by all early GM products, beginning with the Chevrolet Superior.
Starting in 1926 through 1958, GM used four different designations based on different wheelbase dimensions used which helped Fisher Body standardize coachwork provided for various bodyshells/platforms with the A-body for Chevrolet, most Pontiacs, Buick, and Oldsmobile vehicles.
The A-body was temporarily suspended in 1958 until it was reintroduced in 1964.
The A-body designation was resurrected in 1964 for a new series of intermediate-sized cars including the Chevrolet Chevelle, Pontiac Tempest, Oldsmobile Cutlass, and Buick Skylark.
The switch in the drive layout spawned the G-body.