For those who think lightweight metals and plastics are new innovations in the auto industry, consider this: Louis Chevrolet won the Indianapolis 500 in 1921 using an engine with magnesium pistons.

The world's first plastic automobile body? Ford Motor Co. developed it in 1941. It showed off a carbon-fiber car in 1977.

Lots of materials have played a profound role in the way vehicles have evolved, but few are truly new.

The technology to curve glass began to change the appearance of windshields -- and the whole car -- in 1953. New glass and glass-bending technology continues to drive new vehicle designs.

Without new chemistries to control the solar energy that reaches the vehicle interior, today's glass-intensive cab-forward designs would not be possible. Laminated "safety glass" was one of the biggest safety improvements ever made.

But by far the most influential material during the auto industry's first 100 years was steel. Not only did it make car bodies stronger, it allowed them to be manufactured far more quickly and efficiently than wood bodies.

Steel was used as early as 1901 in Europe and 1903 in the U.S. for "paneling" the outside of vehicles. But true revolution came with Edward G. Budd, founder of The Budd Co., who invented and patented the all-steel car body in 1912.

Dodge was the first large company to adopt the Budd principle, based on its experience with railroad cars in the early 1920s. It became the standard construction method over the next several years.

Steel remains the predominant body material today, making up about 55% of the total weight of a typical vehicle, but it has undergone many transformations.

Competition from lightweight, alternative materials, downsizing and the switch from body-on-frame to unibody construction caused steel to lose a huge amount of business -- in total pounds -- from Detroit during the '70s. But steel's share of total vehicle body weight only has dropped about 5% since 1976.

New alloys and processing techniques have created lighter-weight, more easily formed steels over the years. Growing competition from plastic body panels led to the development of zinc-coated rust-resistant steels still being refined today.

Aluminum has fought with steel for auto bodies since the dawn of the industry. Aluminum actually was the preferred material for auto body panels before the 1920s because of its ductility. Complex body frame sections also often were made from aluminum castings in the early 1900s, just as they are today in some advanced aluminum body structures.

The invention of the first sheet-metal presses gave steel the edge in the 1920s in body structures, but aluminum has continued to find successful niches.

Plastics first saw use in car interiors in the 1920s. First exterior use was in the late '40s when metal parts coated with simulated wood-grain vinyl replaced real wood veneers on outside sheet metal for the classic "woody" look. By the 1960s, vinyl took over vehicle interiors.

On Nov. 2, 1940, Henry Ford demonstrated with an axe how a new plastic material made largely from soybeans and fashioned in the shape of a deck lid for a 1941 Ford could resist direct blows. The following year, on Aug. 13, 1941, the world's first experimental plastic automobile body was completed in Dearborn, MI. But the research never led to a production car.

Glass-fiber reinforced resin was first used to manufacture boat hulls in California shortly before the end of WWII. Several promising experiments were made to adopt the process for car bodies as early as 1944, but nothing happened until General Motors Corp. design chief Harley Earl saw the material used on a Jeep-type vehicle called the Brooks Boxer in 1952.

He saw the new material as a perfect medium for turning fragile clay design studies into more durable prototypes. Using the new material, Mr. Earl produced a sports car prototype in only three months. Less than a year later, the Corvette was in full-scale production, still using the glass-fiber reinforced plastic body.