Brakes have gone through a lot of change since the 19th century.
Before the internal combustion engine, horse drawn carriages were usually equipped with cable actuated, rubber shoe disc brakes to help stabilize the carriage when the horses slowed down. The increased speed enabled by the advent of electric motors, steam and gasoline engines brought with it an increased demand for braking power and consistency.
Genesis
Ransom E. Olds opened the doors to the Olds motor company in 1897, with the sole intent of producing the first mass produced, low priced car in America. Olds' first car was capable of a thunderous 14 mph, which necessitated a more powerful braking system than the buggy types used on contemporary automobiles. However, its mission statement demanded a cheap one. Olds solved the problem by wrapping a long steel strip around a drum connected to the axle. The strip was connected to the chassis on one end and the hand-actuated brake lever on the other. When the driver pulled the lever, the strip tightened the strip on the drum and slowed the car.
Drum Brakes
The next evolution in brakes wasn't so much one of design as it was materials, and actually represented a sort of regression. While Olds' external drum brake was fairly powerful, it quickly revealed its fatal flaw--because the drum was exposed to dirt and water, it would often slip when wet and wore out very quickly. Automakers returned to buggy-type internal drum brakes, where the drum is hollow and uses a set of shoes on the inside to press against its internal surface. However, advances in material science allowed automakers to move away from the inadequate rubber brake pads once used; semi-organic and asbestos brake pads lasted longer and worked better. This design remained dominant in the U.S. till the mid 1970's, when disc brakes came on the scene.
Hydraulic Brakes
In 1918, a promising young engineer named Malcolm Lougheed (who later changed his name to Lockheed and founded the eponymous aircraft company) designed a hydraulic brake system for use on automobiles. Prior cable-actuated brakes were prone to sticking and seizing when corroded, and ensuring braking application at all four wheels simultaneously was almost impossible. Hydraulic brakes were easier to modulate, and provided more force per square inch than mechanical systems.
Anti-Lock Brakes
Anti-lock braking systems sense when one wheel stops moving (locks under braking), and reduce brake pressure to that wheel until it starts turning again. Although anti-lock braking systems were first developed by French aircraft engineer Gabriel Voisin in 1929, electronic anti-lock systems as we know them today weren't introduced until the Bendix "Sure Brake" system used in 1971 Chrysler Imperials and GM's "Trackmaster" equivalent used in rear-drive Caddies.
Stability Control
Stability control systems use steering wheel input, yaw (sideways movement) sensors and suspension sensors to determine where the driver wants the car to go relative to what it's actually doing. If the computer determines the car is excessively understeering or oversteering, it will apply braking force to the tires on the inside of the turn to turn the car sharper or the outside of the turn to straighten it out. Mitsibishi introduced the first stability control systems in their 1990 Diamante, and a Mercedes/Bosch partnership refined a similar system in 1995. Most modern stability control systems are based on the Mercedes/Bosch design.
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