What is the primary function of a proxy server?

The primary function of a proxy server is to act as an intermediary between a user's device and the internet. It serves to facilitate connections by receiving requests for data from clients (such as web browsers), forwarding these requests to the appropriate external servers, and then returning the data back to the clients. This process not only enables users to access content on the internet but also allows for various functionalities such as anonymity, content filtering, and caching.

When considering alternative functions listed in the other choices, while connecting with other computers is part of what a proxy server does, it is not its sole or primary function. For example, proxy servers can also be used to improve internet speed through caching (storing frequently accessed content), analyze network traffic to monitor and log requests, and in some cases, function as a backup mechanism. However, the essence of a proxy server is in its role as a connector and facilitator, enabling communication between users and online resources.