Variants of codes and indecomposable languages

We continue the investigation of representing a language as a catenation of languages, each of which cannot be further decomposed in a nontrivial fashion. We study such prime decompositions, both finite and infinite ones. The notion of a length code, an extension of the notion of a code leads to general results concerning decompositions of star languages. Special emphasis is on the decomposition of regular languages. Also some open problems are mentioned.