Debounce vs. Throttle in JavaScript

Debounce postpones execution until calls have stopped for a configured quiet period; it is useful for search suggestions, autosave, and resize work where only the final input matters. Throttle allows at most one call per interval; it is useful for scroll position, pointer movement, and telemetry where periodic updates are valuable. A robust implementation stores the latest arguments and receiver, owns one timer, and defines whether it supports leading calls, trailing calls, cancel, and flush. In a component, cancel outstanding work during unmount so a stale callback cannot update disposed state. Do not claim one is universally better: choose debounce when the final value is the useful one and throttle when bounded-rate feedback is needed. Test a single call, a burst, calls exactly on the boundary, cancellation, and both leading/trailing settings.

Complexity: For n incoming events, the wrapper performs O(n) bookkeeping time and O(1) auxiliary space, while it deliberately bounds downstream calls by the configured interval.