For networking, id Tech 3 uses a "snapshot" system to relay information about game "frames" to the client over UDP. The server attempts to omit as much information as possible about each frame, relaying only differences from the last frame the client confirmed as received (Delta encoding). "id Tech 3" uses a virtual machine to control object behavior on the server, effects and prediction on the client and the user interface. This presents many advantages as mod authors do not need to worry about crashing the entire game with bad code, clients could show more advanced effects and game menus than was possible in "Quake II" and the user interface for mods was entirely customizable. Unless operations which require a specific endianness are used, a QVM file will run the same on any platform supported by "Quake III Arena." The engine also contains bytecode compilers for the x86 and PowerPC architectures, executing QVM instructions via an interpreter.