1. A system comprising: a web server, wherein the web server is not a proxy server; the web server comprising a processor and a memory; and a module on the web server configured to cause the processor to: receive a communication comprising a secure or non-secure HTTP GET or POST command from a host computer requesting a session on the web server; in response to receiving the communication, establish the session on the web server and assign a session-specific identifier to the session; receive an HTTP POST or GET command from the host computer to receive an encoded screen image from the host computer using a codec; receive a communication comprising an HTTP GET or POST command from a client computer requesting to join the session on the web server; send to the client computer the encoded screen image via an HTTP POST or GET command; receive a device input event originating at the client computer via an HTTP POST or GET command; and send to the host computer the device input event via an HTTP POST or GET command, the device input event being processed at the host computer to enable the client to act as master for input device input of the host computer.