What is the function of cookies in web browsing?

The function of cookies in web browsing is primarily to store user data within a web browser. Cookies are small pieces of data that websites save on a user's device to remember information about the user's visit. This can include login credentials, user preferences, and tracking information for analytics purposes.

By storing this data, cookies enhance the user experience by allowing for personalized interactions with the website. For instance, when a user returns to a site, the stored cookie data can be used to automatically log them in or present tailored content based on their previous interactions. This is essential for functionalities like shopping carts, user settings, and session management, making cookies a crucial component of modern web browsing.

The other options provided are related to different aspects of web technology but do not accurately describe the primary purpose of cookies. For instance, enhancing website design pertains more to user interface and experience elements rather than data storage. Mapping domain names to IP addresses is a function of Domain Name System (DNS) records, and redirecting users to new sites involves URL forwarding or HTTP redirection, which is unrelated to the primary role of cookies.