The copy is updated on a timed interval, or when a change on screen is noticed by the remote control software.
The controlling computer (referred to in this context as the client) displays a copy of the image received from the controlled computer's (in this context the server) display screen. Remote desktop virtualization implementations operate as client/server computing environments. There are various professional first-party, third-party, open source, and freeware remote desktop applications, some of which are cross-platform across various versions of Windows, Mac OS X, UNIX, and Linux. This is widely used by many computer manufacturers and large businesses' help desks for technical troubleshooting of their customers' problems. Remote access can also be explained as remote control of a computer by using another device connected via the internet or another network.