Distributed computing is a field of computer science that studies distributed systems. A distributed system is a system whose components are located on different networked computers, which communicate and coordinate their actions by passing messages to one another from any system. The components interact with one another in order to achieve a common goal. Three significant characteristics of distributed systems are: concurrency of components, lack of a global clock, and independent failure of components. It deals with a central challenge that, when components of a system fails, it doesn't imply the entire system fails. Examples of distributed systems vary from SOA-based systems to massively multiplayer online games to peer-to-peer applications.