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Sultan Akhter
Sultan Akhter

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Understanding Javascript Closures (Without Breaking a Sweat!)

JavaScript is full of fascinating concepts, but few are as enchanting (and sometimes perplexing) as closures. If you’ve ever scratched your head wondering what closures are, you're in the right place. By the end of this two-minute read, you'll be able to dazzle your friends with your newfound knowledge. Ready? Let’s dive in!

What Exactly is a Closure?

In JavaScript, a closure is like a backpack. Imagine a function packing its variables and taking them along wherever it goes, even after the outer function has finished executing. This ability to remember and access its lexical scope is what makes a closure.

Why Should You Care About Closures?

Closures are everywhere in JavaScript. They are crucial for creating powerful and efficient code, especially when dealing with asynchronous operations, callbacks, and functional programming. Mastering closures can elevate your JavaScript skills from “meh” to “wow!”

The Closure Magic Show

Let’s break it down with a simple example:

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Here’s what’s happening:

  1. Outer Function: 'outerFunction' defines a variable 'outerVariable' and an 'innerFunction'.

  2. Inner Function: 'innerFunction' has access to 'outerVariable' even after 'outerFunction' has executed.

  3. Closure in Action: When 'myClosure' is called, it remembers the environment in which it was created, logging "I’m the outer variable!".

Common Uses for Closures

1. Data Privacy:

Closures can help keep variables private and protect them from the outside world. Think of them as JavaScript’s version of a “Do Not Disturb” sign.

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2. Creating Factories:

Closures are perfect for factory functions, where you need to create multiple instances of a function with their own private state.

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Conclusion

Closures might sound like magic, but they are a fundamental part of JavaScript that can make your code more efficient and powerful. Remember, a closure is simply a function bundled together with its surrounding state (the lexical environment). So, next time you see a closure in action, give yourself a pat on the back – you’ve just witnessed some JavaScript wizardry!

Happy coding, and may your closures always be tight!

If you want to learn/revise about the basics of Javascript, follow me and checkout some other articles related to the basic concept of Javascript.

Top comments (22)

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wizard798 profile image
Wizard

Nice explanation, nicely explained everything

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Sultan Akhter

I'm delighted you liked it.

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wilmela profile image
Wilmela

Very simple and clear.
Thanks javascript wizard. Lol

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i-sultan0 profile image
Sultan Akhter

Thanks! always here to assist you.

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Ayush Kumar Shaw

Quite a nice writeup Sultan! You very beautifully explained the critical JavaScript concept of closures. Thanks. I had fun reading it. 🤗

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Sultan Akhter

Glad you like it.

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Adam Jamiu • Edited

Concised and informative. Thanks lad 👍

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Sultan Akhter

I am glad you liked it.

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Tanmoy Sinha

Awesome Content!

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Sultan Akhter

Thanks.

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ghufran_baig_c46f561390d0 profile image
Ghufran Baig

Very nice and concise writeup add huge clarity with simple examples. Thank you

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Sultan Akhter

I'm glad it resonated with you.

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benjamin_benkert_eec40f3b profile image
Benjamin Benkert

Well that was simple and easy to understand. Thanks!

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Sultan Akhter

It's great to hear you liked it

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IT Flashcards

That was well explained. Every beginner JS programmer should have no problem understanding what closures are. 👍

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Sultan Akhter

It's wonderful to know you liked it.

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Andrew Saeed

Well explained! Nice work!

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Sultan Akhter

Thanks.

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Clever AKANIMOH

Nice article ❤️👍

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Sultan Akhter

Thanks.