A "server" is a computer or array of computers that supply a service such as a game server that hosts games. In Travian there are tens servers that supply certain regions which use local urls such as .hk, .de, .cn, .us, and .uk; .pk; and then there are international servers which have a url that ends in .com.
The "end of the server" implies the time when the server resets the game it is running, which for normal servers has about a 12-18 month cycle but is dependent on how quickly a World Wonder is built and at what time the Natars are released.
