JavaScript Category

EVENT LOOP

Scheduler for async tasks in JS runtimes.

Definition

The event loop coordinates call stack work and queued callbacks so non-blocking JavaScript can process timers, I/O, and microtasks without freezing the main thread.

Practical Example & Use Case

Teams debugging delayed UI updates often inspect whether long synchronous code blocks are blocking the event loop and starving pending render tasks.

Editorial review date: 2026-03-10

Interactive Practice

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