A stopwatch is a handheld device used to measure the amount of time elapsed from a specific starting point. It typically features buttons to start, stop, and reset the timer, allowing users to track time accurately for various activities, such as sports, cooking, or experiments. Most stopwatches display time in hours, minutes, seconds, and fractions of a second. They can be digital or analog, with digital stopwatches often providing additional features like lap timing and memory functions. Athletes, coaches, and scientists commonly use stopwatches to monitor performance and conduct precise measurements.