πThe Event Loop β Mastering Async Behavior in JS


π€― Why JavaScript Feels Asynchronous
JavaScript is single-threaded β it runs one task at a time.
But when Hasnide uses things like:
setTimeout()
fetch()
Promises
async/await
β¦it feels asynchronous. That magic is made possible by the event loop.
π§ Key Components
β 1. Call Stack
The main place where JavaScript executes functions.
LIFO (Last-In, First-Out) stack.
β 2. Web APIs / Browser APIs
Things like setTimeout
, DOM events, fetch()
are handled by the browser β not the JS engine itself.
β 3. Callback Queue / Task Queue
Once the Web API finishes, the callback is placed into the callback queue.
β 4. The Event Loop
This loop constantly checks:
Is the call stack empty?
If yes β push the next callback from the queue into the stack.
This allows JavaScript to remain non-blocking and responsive.
π Visual Timeline
π§ͺ Code in Action
π Stack vs Queue vs Microtasks
β Summary
βοΈ Written By
π« chaitanyachopde14@gmail.com
π Inspired By
Real-world DevSync training exercises
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Written by

Chaitanya Chopde
Chaitanya Chopde
Hey, I'm Chaitanya Chopde π» Web Development Learner | Frontend Focused π οΈ Learning HTML, CSS, JavaScript & Figma βοΈ Writing to share my dev journey, tips & projects π·οΈ #DevsyncLearning | Building one line of code at a time