Reo is a domain-specific language for programming and analyzing coordination protocols that compose individual ''processes'' into full ''systems'', broadly construed.
Examples of classes of systems that can be composed with Reo include component-based systems, service-oriented systems, multithreading systems, biological systems, and cryptographic protocols.
Reo has a graphical syntax in which every Reo program, called a ''connector'' or ''circuit'', is a labeled directed hypergraph.
Such a graph represents the data-flow among the processes in the system.
Reo has formal semantics, which stand at the basis of its various formal verification techniques and compilation tools.
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