Collaborative computing/Distributed system
A distributed system appears like a single system to the user, when in fact it is not: "The key distinction is that in a distributed system, a collection of independent computers appears to its users as a single coherent system (Tanenbaum, 2011:2)." The most well-known distributed system is the World Wide Web (WWW), which runs on the Internet, but appears to the user as a single coherent system (a web-page).
In literature there is confusion about the differences between a distributed system and a computer network. Unlike in the distributed system, a computer network exposes the user to the different machines and makes no attempt to make the machines look and act in a coherent way. In fact, distributed systems rely on services and protocols provided by computer networks. Distributed systems are formed by independent machines which orchestrate their operation via messages flowing through those computer networks.