Ubiquitous Language

By using the model-based language pervasively and not being satisfied until it flows, we approach a model that is complete and comprehensible, made up of simple elements that combine to express complex ideas.

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Domain experts should object to terms or structures that are awkward or inadequate to convey domain understanding; developers should watch for ambiguity or inconsistency that will trip up design.

-- Eric Evans

Market

Each market is a contract that participants agree to. It is a set of rules that govern the interactions between the participants.