Both return a Server object ($this->getServer() & Server::getInstance()). Basically the same thing, but for some reason @PEMapModder recommends $this->getServer due to some potential issues with static objects? (Forgot what he said exactly, but something like that) Also, $this->getServer() requires an Plugin instance, while Server::getInstance can be almost called everywhere. Please contribute something useful to the thread. This question is not exactly facepalm worthy...