🎯 Scope in JavaScript — The Complete Guide
Category: js / general-concepts
Difficulty: hard
Interview Importance: 🔴 Critical — Scope is fundamental to JavaScript. Questions about scope, hoisting, and closures appear in 95% of technical interviews and are essential for debugging complex issues 1️⃣ What is Scope? Scope is the set of rules that determines how and where variables can be accessed in your code. It defines the visibility and lifetime of variables and functions, preventing naming conflicts and managing memory efficiently. The Core Concept [code example] Real-World Analogy: The House 🏠 Think of scope like a house with different rooms: [code example] Simple Example ```javascript // Global scope - accessible everywhere const globalVar = 'I am global'; function parentFunction() { // Function scope - accessible inside this function const parentVar = 'I am in parent function'; if (true) { // Block scope - accessible only inside this block const blockVar = 'I am in block';...