What is the primary role of a web server?

The primary role of a web server is to store, process, and deliver web pages to clients. When a user requests a webpage by entering a URL into a browser, the web server retrieves the requested web page, processes any necessary server-side scripts, and sends the page's HTML, CSS, and any other resources back to the client (i.e., the user's web browser). This process enables users to view and interact with websites over the internet.

The other options describe different roles that are not the primary function of a web server. Developing mobile applications is the domain of application developers and requires different tools and environments. Storing user data locally is typically managed by client-side applications or databases rather than a web server. Designing web graphics and layouts falls under the skills of web designers, who focus on the visual aspects of websites rather than the server's role in delivering content.