The automotive industry comprises a wide range of companies and organizations involved in the design, development, manufacturing, marketing, selling, repairing, and modification of motor vehicles. It is one of the world's largest industries by revenue (from 16% such as in France up to 40% in countries such as Slovakia).

The automotive industry began in the 1860s with hundreds of manufacturers pioneering the horseless carriage. Early car manufacturing involved manual assembly by a human worker. The process evolved from engineers working on a stationary car to a conveyor belt system where the car passed through multiple stations of more specialized engineers. In the 1960s, robotic equipment was introduced, and most cars are now mainly assembled by automated machinery.

For many decades, the United States led the world in total automobile production, with the U.S. Big Three General Motors, Ford Motor Company, and Chrysler being the world's three largest auto manufacturers for a time, and GM and Ford remaining the two largest until the mid-2000s. In 1929, before the Great Depression, the world had 32,028,500 automobiles in use, of which the U.S. automobile enterprises produced more than 90%. At that time, the U.S. had one car per 4.87 persons. After 1945, the U.S. produced around three-quarters of the world's auto production. In 1980, the U.S. was overtaken by Japan and then became a world leader again in 1994. Japan narrowly passed the U.S. in production during 2006 and 2007, and in 2008 also China, which in 2009 took the top spot (from Japan) with 13.8 million units, although the U.S. surpassed Japan in 2011, to become the second-largest automobile industry. In 2023, China had more than 30 million produced vehicles a year for the first time in history, after reaching 29 million for the first time in 2017 and 28 million the year before. From 1970 (140 models) to 1998 (260 models) to 2012 (684 models), the number of automobile models in the U.S. has grown exponentially.

In 2007, there were about 806 million cars and light trucks on the road, consuming over 980 billion liters (980,000,000 m 3 ) of gasoline and diesel fuel yearly. The automobile is a primary mode of transportation for many developed economies. In developed countries, the automotive industry has slowed, a trend expected to continue, especially as the younger generations of people (in highly urbanized countries) no longer want to own a car, and prefer other modes of transport. Other potentially powerful automotive markets are Iran and Indonesia. Emerging automobile markets already buy more cars than established markets.

According to a J.D. Power study, emerging markets accounted for 51% of the global light- vehicle sales in 2010. The study, performed in 2010 expected this trend to accelerate. However, more recent reports (2012) confirmed the opposite; namely that the automotive industry was slowing down even in BRIC countries. In the United States, vehicle sales peaked in 2000, at 17.8 million units. In July 2021, the European Commission released its "Fit for 55" legislation package, which contains important guidelines for the future of the automotive industry; all new cars on the European market must be zero-emission vehicles from 2035.

The governments of 24 developed countries and a group of major car manufacturers including GM, Ford, Volvo, BYD Auto, Jaguar Land Rover and Mercedes-Benz committed to "work towards all sales of new cars and vans being zero emission globally by 2040, and by no later than 2035 in leading markets". Major car manufacturing nations like the United States, Germany, China, Japan and South Korea, as well as Volkswagen, Toyota, Peugeot, Honda, Nissan and Hyundai, did not pledge.

Trucks' share of US vehicles produced, has tripled since 1975. Though vehicle fuel efficiency has increased within each category. The new trends are hybrid and electric vehicles.