In linguistics, coordination is a frequently occurring complex syntactic structure that links together two or more elements, known as conjuncts or conjoins. The presence of coordination is often signaled by the appearance of a coordinator (coordinating conjunction), e.g. and, or, but (in English). The totality of coordinator(s) and conjuncts forming an instance of coordination is called a coordinate structure. The unique properties of coordinate structures have motivated theoretical syntax to draw a broad distinction between coordination and subordination. Coordination is one of the most studied fields in theoretical syntax, but despite decades of intensive examination, theoretical accounts differ significantly and there is no consensus about the best analysis.