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Electric watch, which commonly means any watch that is powered by electricity, has become a generic term for the first generation of electrically powered watches which appeared starting in 1957, before the invention of quartz watches in the 1970s. Their timekeeping element was either a traditional balance wheel or a tuning fork, driven electromagnetically by a solenoid powered by a battery. The hands were driven mechanically through a wheel train. They were superseded by quartz watches, which had greater accuracy and durability due to their lack of moving parts. Recent automatic quartz watches, which combine mechanical technology with quartz timekeeping, are not included in this classification.
http://en.wikipedia.org/wiki/Electric_watch
[edit] Electronic movements
See also: Electric watch
Electronic movements have few or no moving parts, as they use the piezoelectric effect in a tiny quartz crystal to provide a stable time base for a mostly electronic movement. The crystal forms a quartz oscillator which resonates at a specific and highly stable frequency, and which can be used to accurately pace a timekeeping mechanism. For this reason, electronic watches are often called quartz watches. Most quartz movements are primarily electronic but are geared to drive mechanical hands on the face of the watch in order to provide a traditional analog display of the time, which is still preferred by most consumers.
The first prototypes of electronic quartz watches were made by the CEH research laboratory in Switzerland in 1962. The first quartz watch to enter production was the Seiko 35 SQ Astron, which appeared in 1969. Modern quartz movements are produced in very large quantities, and even the cheapest wristwatches typically have quartz movements. Whereas mechanical movements can typically be off by several seconds a day, an inexpensive quartz movement in a child's wristwatch may still be accurate to within half a second per day—ten times better than a mechanical movement
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