Improvements in manufacturing such as the tooth-cutting machine devised by Robert Hooke allowed some increase in the volume of watch production, although finishing and assembling was still done by hand until well into the 19th century.
A major cause of error in balance wheel timepieces, caused by changes in elasticity of the balance spring from temperature changes, was solved by the bimetallic temperature compensated balance wheel invented in 1765 by Pierre Le Roy and improved by Thomas Earnshaw.
They generally incorporate timekeeping functions, but these are only a small subset of the smartwatch's facilities. Watches evolved from portable spring-driven clocks, which first appeared in 15th century Europe.
Dating a pocket watch
Today most inexpensive and medium-priced watches, used mainly for timekeeping, have quartz movements.
Expensive collectible watches, valued more for their elaborate craftsmanship, aesthetic appeal and glamorous design than for simple timekeeping, often have traditional mechanical movements, even though they are less accurate and more expensive than electronic ones.
The lever escapement was the single most important technological breakthrough, and was invented by Thomas Mudge in 1759 and improved by Josiah Emery in 1785, although it only gradually came into use from about 1800 onwards, chiefly in Britain.
The British had predominated in watch manufacture for much of the 17th and 18th centuries, but maintained a system of production that was geared towards high quality products for the elite.
Time-related features such as timers, chronographs and alarm functions are common.
Some modern designs incorporate calculators, GPS and Bluetooth technology or have heart-rate monitoring capabilities.
A watch is a small timepiece intended to be carried or worn by a person.
It is designed to keep working despite the motions caused by the person's activities.
The oldest surviving wristwatch (then described as a bracelet watch) is one made in 1806 and given to Joséphine de Beauharnais.