stopwatch

A stopwatch is not for telling the time of day. It is for measuring how long something takes. Think of a runner crossing the finish line, or a cook timing how long to boil an egg. Unlike a regular clock, it starts and stops when you tell it to, so you can measure a short period of time.

You might use one in a science experiment to measure reaction time, or a coach might use one to time laps. Many are digital now, but people also picture a small handheld device with buttons to start, stop, and reset. It is useful anywhere you need to track how long an action or event lasts.

A stopwatch is a device used to measure elapsed time, which is the amount of time that passes between a start point and a stop point. While a clock tells you the time of day, a stopwatch tells you how long something lasts.

Older ones were mechanical, with gears and springs inside, but most modern ones are digital. They usually have buttons to start, stop, and reset. Some also let you record lap times or split times, which helps when you want to track parts of a longer event.

People use stopwatches in many situations. In sports, they help measure races, sprints, workouts, and practice drills. In science, they are useful when an experiment depends on exact timing. In cooking, they help track boiling, baking, or resting times. They can also be used in daily life to time study sessions, tasks, games, or anything else that begins and ends.

So the idea is simple: when you want to know not what time it is, but how much time has passed, a stopwatch is the tool you use.