Module type with Schreier technique and flat localizations as unifying concept with toolkit

We call attention and pay admiration to the fundamental work of W. Leavitt on module type of rings. In particular we present a new approach to Leavitt path algebras by using flat bimorphic rings of quotients. It turns out that module type becomes a unifying concept where different algebraic principles, areas are connected via Schreier technique and flat localizations.