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🔡 JavaScript Variables

📌 What are JavaScript Variables?

📌 JavaScript variables are used to store data values. You can declare them in different ways:

  • 🔹 Automatically
  • 🔹 Using var
  • 🔹 Using let
  • 🔹 Using const

📍 var Keyword

  • 📅 The var keyword was used in all JavaScript code from 1995 to 2015.
  • ✨ The let and const keywords were added to JavaScript in 2015.
  • ⚠️ Use var only for older browsers.
Example02
⚡Code Cell
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Output

📍 let Keyword

  • ❌ Variables defined with let cannot be redeclared.
  • ✅ Must be declared before use.
  • 📦 Has block scope.
Example03
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Output

📍 const Keyword

  • ❌ Variables with const cannot be redeclared or reassigned.
  • 📦 Has block scope.
Example04
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Output

📦 JavaScript Variable Keywords

AttributeDescription
var✅ Can be redeclared and updated. Has function or global scope. Use in legacy code.
let⚠️ Cannot be redeclared, but can be updated. Has block scope.
const🔒 Cannot be redeclared or updated. Must be initialized. Has block scope.

🧠 Test Your Knowledge

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