Introduction to JavaScript: JavaScript is a powerful and widely-used programming language that is primarily used for web development. It provides the ability to add interactivity and dynamic elements to websites, making them more engaging and responsive. JavaScript is supported by all major web browsers and can be used on both the client side (in the browser) and the server side (with the help of platforms like Node.js). With JavaScript, you can create interactive forms, validate user input, manipulate and update content on web pages, handle events triggered by user actions, communicate with servers to retrieve or send data, and build complex web applications. Including JavaScript in an HTML file: To include JavaScript code in an HTML file, you have multiple options. The most common method is to use the <script> tag, which allows you to embed JavaScript code directly into your HTML file or link to an external JavaScript file. Inline JavaScript: You can write JavaScri...