Service-oriented architecture (
SOA) is a
software design and software architecture design pattern based on structured collections of discrete software modules, known as services, that collectively provide the complete functionality of a large software application.. Purpose of SOA is to allow easy cooperation of a large number of computers that are connected over a network. Every computer can run an arbitrary number of programs - called services in this context - that are built in a way that they can exchange information with any other service within the reach of the network without human interaction and without the need to make changes to the underlying program itself.
In a large network of computers SOA has the same role and duties as the traditional operating system on a single computer. Consequently SOA is designed in analogy to traditional multi-tasking operating systems like Windows, Unix, zOS etc.