Karl Benz made one of the very first cars in the 1880s, and it could go only about 10 miles per hour at best. His 1886 Patent-Motorwagen had three wheels and a rear-mounted, single-cylinder four-stroke engine of about 0.95 liters. It made about 0.6 horsepower, and Benz applied for a patent on 29 January 1886 for his motor vehicle. The patent paper is now called the automobile's 'birth certificate.'

Before 1913, workers built each car by hand while it stayed in one place. That changed in October 1913, when Henry Ford's moving assembly line first ran at his Highland Park plant in Michigan. A rope pulled each car past the workers, and each worker did one job.

Ransom Olds had built cars on an assembly line before Ford did, and Ford's moving line combined ideas from still assembly lines like the one Olds used. Olds sold his small Curved Dash car for $650 in 1901. In March 1901 a fire burned Olds's Detroit car factory to the ground, yet by the end of that year Olds had still built 425 Curved Dash cars. Olds's 'progressive assembly' put each chassis on a stand with casters. The car was moved from station to station by hand, rope or chain, so it was a line, but not a continuous, powered one.

Ford also borrowed from older industries when he made his line. Writers point to meatpacking and brewing, where work already moved past workers who each did one job. Ford first tried the line on a small part, a magneto, which took 20 minutes to build before the line and only five minutes after it.

A rope and winch pulled the chassis of each Model T along a short track while workers added parts as it passed. After the 1913 trial with a rope and winch, Ford added a powered conveyor, and the line kept being rebuilt and improved. The moving line kept getting faster. At first it cut the time to build a Model T from 12.5 hours to under 6, and within a year it was down to 93 minutes.

Ford's line combined standard parts with more efficient assembly. Together they raised output per worker and let Ford cut the cost and price of the Model T. Henry Ford wanted to make cars that ordinary families could buy. A new Model T cost $850 when it first came out, and later the price fell to $260, so many more families could buy one. About 15 million Model Ts were built before the car was dropped in 1927.

The work on a moving line was monotonous. Ford's workers quit and missed work in large numbers, which was part of why he raised pay. In 1914 Ford began paying workers $5 a day, more than twice what most carmakers paid. Historians do not agree on one reason for the $5 day. Accounts say it was to keep workers who might quit, to hire better and steadier workers, or both. Ford's high pay was later described as part of a 'virtuous cycle': when workers get more productive, wages can rise, and workers then have more money to buy products.

A car plant runs several workshops in a row: a press shop that starts the process, a body shop, a paint shop and assembly halls. In the press shop, big presses squeeze flat metal into the shapes of car parts such as doors and side panels. Cars are built in very big factories, where people and machines make many cars every day. A BMW plant in South Carolina builds more than 1,500 vehicles every day.

A car is made of thousands and thousands of parts, but the number depends on how you count. What counts as a 'part' changes the answer. A car has about 30,000 parts if you count every screw, nut and bolt, and counting every fastener gives 20,000 to 30,000 parts, while counting only major pieces gives under 2,000.

Every new car starts as a drawing. Car design takes a long time because a car is tested in many forms: sketches, small models, full-size clay and then physical prototypes. A new car model takes about three years or more from the first sketch until it is on the factory line.

Ford was not the first carmaker to use an assembly line. What was new in 1913 was a line that moved the car to the workers. Today cars still move along a line from station to station while workers and machines add parts to them.

Words to know

• chassis: car's base frame
• conveyor: moving belt
• monotonous: dull, repetitive
• magneto: small engine part