Knowledge compilation is a family of approaches for addressing the intractability of a number of artificial intelligence problems.
A propositional model is compiled in an off-line phase in order to support some queries in polytime. Many ways of compiling a propositional models exist. Among others: NNF, DNNF, d-DNNF, BDD, SDD, MDD, DNF and CNF.
Different compiled representations have different properties. The three main properties are: