Main Page | See live article | Alphabetical index In computer science a regular grammar is a formal grammar (N, Σ, P, S) such that all the production rules in P are of one of the following forms: A -> a where A a non-terminal in N and a a terminal in Σ A -> aB where A and B in N and a in Σ A -> ε where A in N. The second form may also be replaced with A -> Ba. An example of a regular grammar G with N = {S, A}, Σ = {a, b, c}, P consists of the following rules S -> aS S -> bA A -> ε A -> cA and S is the start symbol. This grammar describes the same language as the regular expression a*bc*. The regular grammars describe exactly all regular languages and are in that sense equivalent with finite state automata and regular expressions. See also: Chomsky hierarchy This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.