📌 JavaScript Event Loop – Explained Simply
JavaScript is a single-threaded language, meaning it can execute only one task at a time.
But then how does it handle things like API calls, timers, and user interactions?
The answer is the JavaScript Event Loop.
🔹 What is the Event Loop?
*The Event Loop is a mechanism that allows JavaScript to:
*
- Execute synchronous code
- Handle asynchronous tasks
- Stay non-blocking
🔹 Main Components of the Event Loop
1️⃣ Call Stack – Executes code line by line
2️⃣ Web APIs – Handles async tasks (setTimeout, fetch)
3️⃣ Callback Queue – Stores completed async callbacks
4️⃣ Event Loop – Moves callbacks to call stack
🔹 Example
`console.log("Start");
setTimeout(() => {
console.log("Timeout");
}, 0);
console.log("End");
Output:
Start
End
Timeout`
Even with 0ms delay, setTimeout runs later because of the event loop.
🔹 Why Event Loop is Important?
✔ Non-blocking behavior
✔ Smooth UI
✔ Efficient async handling
🔹 Conclusion
The JavaScript Event Loop is the heart of asynchronous programming and is essential for writing efficient JS code.
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