An automatic watch movement uses the natural motion of the wearer to provide energy to wind the mainspring.
Origins
It is believed that the Swiss watchmaker Abraham-Louis Perrelet invented the first automatic watch movement in the 1770s. However, it was only after WWII that automatic watch movements became more popularized.
John Harwood, a watch repairer from England, patented the automatic wristwatch in 1928 and began producing them in a factory in Switzerland.
Charateristics
Due to the high level of craftsmanship and precise engineering involved, automatic movement watches are considered very sophisticated and sought-after. This type of mechanism is typically used in premium and luxury watches.
Automatic watches do not source their energy from batteries. They utilize a self-winding mechanism that can power itself independently throught the movements of the wearer's hand. If an automatic watch is not worn and runs out of its mechanical power, it can also be wound manually using the stem.