Timeinterval

TimeInterval is a quantity used to represent a duration or the length between two moments in time. It is typically expressed as a non-negative amount of time, most commonly in seconds. In many programming environments, a TimeInterval is a real number, enabling fractional seconds (for example, 0.25 for a quarter of a second or 2.75 seconds). Some languages distinguish between a duration and a specific time window, using types such as TimeInterval, Duration, or TimeSpan.

In programming practice, TimeInterval can denote either a duration to elapse (a timer length) or the span between two time points when used with timestamps. When measuring elapsed time, developers often prefer monotonic clocks to prevent changes to the wall clock from affecting calculations. TimeInterval values are commonly used for delays, timeouts, animation durations, and scheduling tasks.

Different ecosystems name and represent TimeInterval differently. In Swift, TimeInterval is a typealias for Double representing seconds. Other environments use similar concepts under different names: Java uses java.time.Duration, .NET uses TimeSpan, and Python uses datetime.timedelta.

Units and conversions are a common consideration. While the numeric value is typically interpreted as seconds, APIs may require milliseconds or other units, so explicit conversion is often necessary for display or interfacing with external systems.

See also: Duration, Time span, Timestamp, Timers.