What is the purpose of JavaScript in web development?

JavaScript plays a crucial role in web development primarily by adding interactivity to web pages. This programming language allows developers to create dynamic content that can respond to user actions, such as clicks, form submissions, or mouse movements. For example, JavaScript enables features like image sliders, interactive forms, live content updates, and animations, enhancing the overall user experience.

Unlike CSS, which is used for styling web pages and controlling the visual presentation, or HTML, which is responsible for structuring the content of a webpage, JavaScript directly manipulates the Document Object Model (DOM) to update the appearance and behavior of a page in real-time. It enables users to interact with the webpage rather than just viewing static content.

While server-side operations are typically managed by languages like PHP, Node.js, or Python, JavaScript's versatility extends beyond just the client side; with the advent of environments like Node.js, it has also become a popular choice for server-side scripting. Nevertheless, its primary function on the client side remains focused on enhancing interactivity and engagement on web pages.