JavaScript

JavaScript (JS) is an object-oriented programming language primarily used to create interactive web pages in the browser. Along with HTML and CSS, it is one of the fundamental web technologies.

Functionality and Use

JavaScript enables websites to respond dynamically without having to reload. After the browser has loaded the HTML and CSS, the Document Object Model (DOM) is constructed, which JavaScript can then modify.

This allows content to be updated, user actions such as clicks to be processed, or data to be reloaded in the background. JavaScript is typically executed directly in the browser, but it can also be used on the server with technologies such as Node.js.

Examples

• Form validation on websites, e.g., checking user input
• Dynamic content reloading without refreshing the page
• Interactive elements such as dropdown menus or sliders
• Real-time updates, e.g., in chats or notifications