What is a proxy server?

A proxy server functions as an intermediary between end users and the websites they visit. This setup allows the proxy server to perform various tasks, such as filtering content, caching data to improve load times, moderating traffic, and enhancing anonymity for the user. When a user makes a request to access a website, the proxy server forwards that request on their behalf, retrieves the data from the internet, and then sends it back to the user. This process keeps the user's real IP address hidden from the website they are accessing, improving privacy and security.

The other options present different concepts that do not define a proxy server accurately. For instance, a server that hosts websites is primarily focused on delivering content to users without any intermediary processing. A direct connection refers to a direct link between two devices, which does not involve the anonymous or filtering services a proxy server provides. Additionally, a firewall serves a different purpose of protecting a network from unauthorized access, rather than facilitating connections between users and web content. Each of these alternatives addresses important aspects of networking, but they do not encapsulate the function and purpose of a proxy server effectively.