Chapter 01 of 76 min read
JavaScript Introduction, Variables & Data Types
Understand let, const, strings, numbers, booleans, and developer console output.
What is JavaScript?
JavaScript is a high-level, interpreted scripting language that brings webpages to life with interactive behaviors, calculations, and server communication.
- const: Declares variables that cannot be reassigned. Use by default.
- let: Declares block-scoped variables that can be reassigned.
- var: Legacy declaration with function scope. Avoid in modern code.
JavaScript Example • Chapter 01
// 1. Variable Declarations
const instituteName = "WeBotApp Academy Guwahati";
const estdYear = 2009;
let currentYear = 2026;
let isPlacementGuaranteed = true;
// 2. Calculations
const yearsOfExcellence = currentYear - estdYear;
// 3. Template Literals & Output
console.log("=== WeBotApp Academy Student Intro ===");
console.log(`Institute: ${instituteName}`);
console.log(`Serving Northeast India for: ${yearsOfExcellence} years`);
console.log(`100% Placement Policy: ${isPlacementGuaranteed ? "Active" : "Inactive"}`);💡 Click "Try in Editor" to run, edit, and experiment with this code in our live split-view environment.100% Live Preview
Key Concepts • Chapter 01
- •Always use const unless you know the variable value must change; then use let.
- •Use backtick template strings (`${variable}`) for clean string interpolation.
- •console.log() is your primary tool for inspecting values in the runtime console.
🎯 Chapter Practice Challenge
Declare a studentName variable and calculate your target graduation year.