Unix is called a(n) ___________ operating system because it can run on a desktop pc or a server. operating systems installed on a single computer are called __________ operating systems. a server, also called a(n) _______________, operating system is a multiuser operating system because it controls a central computer that can support many users. a(n) ______________ operating system has features similar to a desktop operating system, but is simpler and significantly smaller. electronic devices such as card readers use ___________ operating systems.