concurrency

Event Loop

The event loop is a concurrency model that runs a single-threaded loop continuously checking for and dispatching events or callbacks. Instead of using multiple threads, it achieves concurrency by never blocking: I/O operations are registered with callbacks and the loop processes completed events one at a time. This model powers Node.js, browser JavaScript, and Python's asyncio. It excels at I/O-bound workloads but can be blocked by CPU-intensive tasks on the main thread.