JS Basics - Class I

Lecture 38 :- JS Basics - Class I 

In "JS Basics - Class I," we'll cover some fundamental concepts and syntax in JavaScript to get you started with the language. JavaScript is a versatile programming language used for web development and much more. Let's dive into some key concepts:

Variables and Data Types: Variables are used to store data. In JavaScript, you can declare variables using let, const, or var (older method). Data types include numbers, strings, booleans, arrays, objects, etc.

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let name = "John"; const age = 30; let isStudent = true; let numbers = [1, 2, 3, 4, 5]; let person = {  name: "Alice",  age: 25, };

Basic Arithmetic: JavaScript supports basic arithmetic operations like addition, subtraction, multiplication, division, and modulus.

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let a = 10; let b = 5; let sum = a + b; let difference = a - b; let product = a * b; let quotient = a / b; let remainder = a % b;

Conditional Statements: Conditional statements help control the flow of the program based on certain conditions. Common ones are if, else if, and else.

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let age = 18; if (age >= 18) {  console.log("You are an adult."); } else {  console.log("You are a minor."); }

Loops: Loops allow you to repeat code multiple times. Common loops are for and while.

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for (let i = 0; i < 5; i++) {  console.log(i); } let counter = 0; while (counter < 5) {  console.log(counter);  counter++; }

Functions: Functions are blocks of code that can be called multiple times. They help in organizing and reusing code.

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function greet(name) {  console.log("Hello, " + name + "!"); } greet("Alice"); // Output: Hello, Alice! greet("Bob"); // Output: Hello, Bob!

DOM Manipulation: JavaScript is used to interact with HTML and manipulate the Document Object Model (DOM).

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// JavaScript const btn = document.getElementById("btn"); const resultDiv = document.getElementById("result"); btn.addEventListener("click", function () {  resultDiv.textContent = "Button clicked!"; });

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<!-- HTML --> <button id="btn">Click Me</button> <div id="result"></div>

This is just the beginning of JavaScript basics. As you progress, you'll learn more complex concepts like objects, classes, asynchronous programming with Promises and async/await, and much more. Practice and experimentation are essential to gaining proficiency in JavaScript.

You can try running the code snippets above in your browser's developer console or in a code editor to see the output. Happy coding! If you have any specific questions or need further explanation on any topic, feel free to ask.