In the context of servers, I have never seen other web hosting platforms use the term "instance," in the context of on-demand server instance vs. just give me a server. While it seems commonplace now, I don't recall reading about other hosting platforms referring to their services as instances. Can you point to literature that does? For instance, from http://aws.amazon.com/ec2/instance-types/ : "You can think of instances as virtual servers that can run applications." That's the AWS context of instances.