xmove is a computer program that allows the movement of X Window System applications between different displays and the persistence of X applications across X server restarts. It solves a problem in the design of X, where an X client (an X application) is tied to the X server (X display) it was started on for its lifetime. Also, if the X server is shut down, the client application is forced to stop running.
xmove lets the client disconnect from its current X server, and connect to a new one, at any time. The transition is completely transparent to the client. xmove works by acting as a proxy between the client and server. It is a "pseudoserver" which stores enough server state so that clients can connect to a new server without being disrupted.