A VPN server is a proxy server—the terms “VPN” and “VPN proxy” are interchangeable. If the proxy server is using HTTPS (also referred to as TLS, previously SSL), then it is actually very similar to a VPN. . A VPN server needs more permissions on the local device than a simple web proxy and, as a result, usually requires users to install a separate app—which is the case for ExpressVPN. Our VPN extension controls our VPN app on your device, which in turn protects all your traffic, not just your browser traffic as a proxy extension would.