Body in white

Body in white (BIW) is the stage in automobile manufacturing in which a car body's frame has been joined together, that is before painting and before the motor, chassis sub-assemblies, or trim (glass, door locks/handles, seats, upholstery, electronics, etc.)

Assembly involves different techniques such as welding (spot, MIG/MAG, or friction stir), riveting, clinching, bonding and laser brazing.

when automobile bodies were made by outside firms on a separate chassis with an engine, suspension, and bumpers attached.

[citation needed] The manufacturers built or purchased wooden bodies (with thin, non-structural metal sheets on the outside) to bolt onto the frame.

Extensive computer simulations of crash-worthiness, manufacturability, and automotive aerodynamics are required before a clay model from the design studio can be converted into a body in white ready for production.