Closures — Free JavaScript Tutorial

Learn Closures in JavaScript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.

Closures — Free JavaScript Tutorial

Learn Closures in JavaScript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.

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TL;DR: Learn Closures in JavaScript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.

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Closures in JavaScript

A closure is when an inner function "remembers" the variables from its outer function even after the outer function has returned.

Every function in JS forms a closure over its surrounding scope.

Use cases: Data privacy (private variables), factory functions, memoization, event callbacks.

Common pattern: outer function returns inner function. Inner function accesses outer's variable (the closure).

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