A proxy server acts as an intermediary between clients (e.g., computers or video cameras) and other servers (e.g., web servers or cloud services), forwarding client requests to other servers and returning the server's response back to the clients. It can provide various functionalities such as caching (to reduce bandwidth and improve response times), access control (to block or allow certain traffic), and anonymity (by hiding client IP addresses). It also enables more complex operations like load balancing, content filtering, and data compression.