✅ Logical Operators in JavaScript – Complete Guide with Real Examples

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📌 Introduction Logical operators help you combine conditions, control flow, and make decisions in JavaScript. In this guide, you’ll learn how to use && , || , and ! effectively with examples and real-world use cases. 🔍 What Are Logical Operators? Logical operators return a boolean value ( true or false ) and are used to evaluate expressions, especially within conditions like if statements. Operator Name Example Description && Logical AND a && b Returns true if both conditions are true || Logical OR a || b Returns true if either condition is true ! Logical NOT !a Reverses the boolean value ✅ 1. Logical AND ( && ) const age = 25; const isCitizen = true; if (age > 18 && isCitizen) { console.log("You can vote!"); } Short-circuiting: If the first condition is false, the second one isn’t evaluated. ✅ 2. Logi...
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What is Hoisting in JavaScript? 🔄 Explained with Example

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📌 What is Hoisting in JavaScript?

In this post, we’ll understand one of the most commonly asked JavaScript interview questions: What is Hoisting? I’ve also added a video below that explains hoisting visually. 👇

Video: What is Hoisting in JavaScript

🔍 What is Hoisting?

Hoisting is a JavaScript mechanism where variables and function declarations are moved to the top of their scope before code execution.

🧠 Think of it like this:

Even if you declare your variables or functions at the bottom of the file, JavaScript will act as if they were declared at the top — but only the declarations, not initializations.

📂 Example 1: Variable Hoisting

console.log(x); // undefined
var x = 10;

🔎 Explanation: The declaration var x is hoisted to the top, but the assignment = 10 is not. So x exists but is undefined at the time of the console.log.

⚠️ Let’s Try with let or const

console.log(y); // ReferenceError
let y = 20;

Note: Variables declared with let and const are also hoisted but are not initialized. They remain in a temporal dead zone until the declaration is encountered.

📘 Function Hoisting

greet(); // "Hello!"
function greet() {
  console.log("Hello!");
}

✅ Function declarations are fully hoisted. So you can call the function before it's defined.

📺 Watch the Video

For a complete breakdown with visuals and explanations, watch the full video above or on YouTube.

🔗 Useful Links

Thanks for reading! If you found this helpful, don’t forget to leave a comment and share this post with fellow developers. 🚀

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