Optimality Theory (henceforth, OT) is a theory of language and grammar that has become quite a popular trend in linguistics after its introduction in 1993 by the phonologist Alan Prince and the cognitive scientist Paul Smolensky (Prince and Smolensky, 1993). In OT a grammar consists of a set of well-formedness constraints. These constraints apply simultaneously to representations of structures that are soft, which means violable. Furthermore the constraints are potentially conflicting and at least an important subset of these constraints is shared by all languages, forming part of Universal Grammar. Individual languages rank these universal constraints differently in their language-specific hierarchies in such a way that higher ranked constraints have total dominance over lower ranked constraints. Possible output candidates for each underlying form are evaluated by means of these constraint rankings. In planning the effect can be soften if we take into account that the softer constraints are often violated.
