There are five big car companies in the world: General Motors, Ford, DaimlerChrysler, Toyota and Volkswagen. But only Toyota relies on one global brand name. All others have a web of subsidiaries spanning the world.

General Motors

General Motors is the world's largest car company, based in Detroit, Michigan. It produces over 8 million cars and trucks a year.

GM was the company that pioneered the development of different brands. In the United States it sells cars under the Cadillac, Chevrolet, Pontiac, Buick, and Oldsmobile labels, and more recently it developed the Saturn as a separate, Japanese-style quality car brand.

GM is one of the largest car producers in Europe, using the Vauxhall badge in the UK and Opel in the rest of Europe. More recently, it acquired a controlling stake in Sweden's Saab Motors, which it continues to operate as a separate brand.

In Australia GM operates one of the country's most well-known brands, Holden. It also has a tie-up with the Japanese car and truck maker Isuzu.

In Latin America the company has a major subsidiary in Brazil, which makes engines and Opel cars.

GM, unique among major car companies, still has its own parts subsidiary, Delphi, which it is expected to spin-off in the near future.

Ford

Ford, the main US rival to GM, is the world's second largest car company, and the most profitable, earning $22bn last year.

The BBC's Richard Griffiths reports on changing times in the global car industry

Unlike GM, it has tended to market cars under its own label - until recently. It was one of the first US companies to set up production abroad, moving to Dagenham in the UK in the 1920s.

In the US it also markets cars under the Lincoln and Mercury labels.

But in recent years it has gone on a buying spree abroad, acquiring luxury carmakers Jaguar and Aston Martin in the UK and a big stake in Japan's number three car company Mazda.

Ford has been highly profitable in recent years and even after its purchase of Volvo it still has a large war chest to fund further acquisitions.

Volkswagen

Volkswagen is trying to transform Skoda

Volkswagen, Germany's largest car maker, has been aggressive in acquiring other car companies throughout Europe.

To complement its own cars and Germany's upmarket Audi brand which it bought in the 1970s, it has spent heavily to acquire the Rolls-Royce car factory, only to be pipped at the post by BMW who will own the brand name after 2003, leaving VW with the Bentley label and the manufacturing plant.

It has moved into Eastern Europe, buying the main car company in the Czech Republic, Skoda, which it hopes to re-invigorate with its own reputation for quality. It operates the SEAT subsidiary in Spain.

Volkswagen has sought out more luxury badges to add to its range, buying up Italy's Lamborghini and Bugatti labels.

The company also produces cars in the United States and Latin America.

DaimlerChrysler

The merger of Germany's Daimler Benz and the US-based Chrysler Corporation created the world's third largest automotive group.

Chrysler markets cars under the Plymouth and Dodge labels, as well as sports utility vehicles under the Jeep badge. It has a very profitable range of minivans or people carriers.

The addition of Mercedes Benz cars gives the group a complete spread of models, from luxury to basic.

DaimlerChrysler has the world's largest truck business, marketing its Mercedes trucks and owning the Freightliner brand in the United States.

DaimlerChrysler has been reported to be in talks to acquire a big stake in Nissan, Japan's second largest car company, in order to boost its presence in Asia.

The rest

On the next rung of the global automotive tree, Fiat now has a monopoly over the old Italian names uniting Alfa Romeo, Ferrari, Maserati and Lancia and its own brand under the same corporate roof.