JavaScript

JavaScript is a high-level programming language that has become one of the fundamental components of modern web applications. All modern browsers include a JavaScript engine that runs any client-side JavaScript code.

When a browser processes an HTTP response containing HTML, the browser creates a Document Object Model (DOM) tree and renders it. JavaScript can access and modify the page's DOM, resulting in a more interactive experience for end users.

A common example where JavaScript could be useful is with client-side validation of a form. Instead of submitting a form to the server and having the server respond with an error, a JavaScript function could check the form first before submitting it to the server.

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