What is the role of JavaScript in web development?

JavaScript plays a crucial role in web development primarily by adding interactivity and dynamic behavior to websites. Unlike HTML, which is used to structure the content of a webpage, and CSS, which is used for styling, JavaScript allows developers to create responsive features that engage users. For example, it can handle user inputs, update content dynamically without reloading the page, create animations, and respond to user actions like clicks or keyboard events.

This interactivity is essential for modern web applications, enabling functionalities such as form validation, interactive maps, and dynamic content loading, which enhance the user experience significantly. JavaScript is an integral part of the web development stack, often working alongside HTML and CSS to create a fully interactive web experience.