What does "event loop" mean in programming?
event loop is one of the most common terms in software development. This guide explains what it means, how it is used in practice, and why it matters, with real examples from the developer world.
Definition
The mechanism that allows JavaScript (and other single-threaded runtimes) to perform non-blocking I/O by offloading operations to the system and handling their results through a queue. The event loop continuously checks if the call stack is empty and processes the next queued callback. Understanding it explains why async code behaves the way it does.
Example
"setTimeout(fn, 0) does not run immediately — it queues the callback in the event loop, so it runs after the current synchronous code finishes."
Related terms
Ready to practice your English at work?
Lingua-e has interactive exercises built around real developer conversations: standups, code reviews, retrospectives, and more. Practice until it comes naturally.
Try Lingua-e for free