What is the primary purpose of JavaScript in web development?

The primary purpose of JavaScript in web development is to add interactive behavior to web pages. JavaScript is a scripting language that enables developers to create dynamic content that responds to user actions, such as clicks, mouse movements, and keyboard input. This interactivity can include anything from validating form entries to animating images or creating responsive user interfaces that adapt to user inputs in real time.

While structuring content is typically the role of HTML, and styling is managed by CSS, JavaScript handles the actions and events that occur on a webpage. It enhances user experience by allowing developers to build applications that are not just static but interactive and engaging. For example, JavaScript can be used to implement features such as drop-down menus, sliders, and interactive forms, which all contribute to a more dynamic user experience.

Managing databases, on the other hand, generally involves server-side languages or technologies that facilitate communication with a database, making it outside the realm of what JavaScript typically handles on the client side. Thus, the recognition of JavaScript's primary role as a tool for interactivity is crucial for understanding its importance in modern web development.