Digital electronic stopwatches are available which, due to their crystal oscillator timing element, they often include date and time-of-day functions as well. Some may have connector for external sensors, allowing the stopwatch to be triggered by external events.
Stopwatch is hand held timepiece designed to measure the amount of time elapsed from particular time when it is activated to the time when the piece is deactivated. A large digital version of designed for viewing at distance, as in sports stadium, is called a stop clock. In manual timing, the clock is started and stopped by a person pressing a button. In fully automatic time, both starting and stopping are triggered automatically, by sensors.
The timing functions are traditionally controlled by two buttons on the case. Pressing the top button starts the timer running, and pressing the button second time stops it, leaving the elapsed time displayed.
Digital electronic are available which, due to their crystal oscillator timing element, they often include date and time-of-day functions as well. Some may have connector for external sensors, allowing the to be triggered by external events, thus measuring elapsed time far more accurately than is possible by pressing the buttons with one's finger. that count by 1/100 of second are commonly mistaken as counting milliseconds, rather than centi seconds. The first digital timer used in organized sports stopwatch was the Digi timer, provided resolution of 1/1000 second. Its first use was in ski racing but was later used by the World University Games in Moscow, The device is used when time periods must be measured precisely and with minimum of complication Laboratory experiments and sporting events like sprints are good.