web javascript

JavaScript is a client-side scripting language primarily used to add interactivity, dynamic behavior, and data manipulation to web pages. It is one of the three core technologies of the web (alongside HTML and CSS) and runs directly in the browser.

Key Concepts in Web JavaScript

1. Basics

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javascript

let name = "Alice"; // Mutable variable

const PI = 3.14; // Immutable constant

2. DOM Manipulation

JavaScript interacts with the Document Object Model (DOM) to modify page content and styles:

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// Select an element

const heading = document.getElementById("myHeading");

// Change content

heading.textContent = "New Heading!";

// Change style

heading.style.color = "blue";

// Create new elements

const newParagraph = document.createElement("p");

newParagraph.textContent = "This is a new paragraph.";

document.body.appendChild(newParagraph);

3. Event Handling

Respond to user actions like clicks, mouse movements, or keyboard input:

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Click Me

4. AJAX & Fetch API

Fetch data from servers without reloading the page (asynchronous requests):

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fetch(")

then(response => response.json)

then(data => console.log(data))

catch(error => console.error("Error:", error));

// Modern approach with async/await:

async function fetchData {

try {

const response = await fetch(");

const data = await response.json;

console.log(data);

} catch (error) {

console.error("Error:", error);

5. Modern JavaScript (ES6+)

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const add = (a, b) => a + b;

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const name = "Alice";

console.log(`Hello, ${name}!`);

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const user = { id: 1, name: "Bob" };

const { id, name } = user;

6. Frameworks & Libraries

7. Security Best Practices

Example: Simple To-Do List

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Add

Learning Resources

JavaScript is essential for modern web development. Start with basics, experiment with *all projects, and explore frameworks as you progress!