Programming methodologies is a complex field, with many methodologies, and names, and many goals and means to reach them: structured programming, programming by refinement, program analysis and verification, refactoring, and many more. Methodologies are developed to enhance one or more programming variable: programming, program speed, reliability, conformance to user/customer needs, reusability, code reuse and sharing, information hiding, etc. Some methodologies are more formal than others, some are embodied in formal tools, programs, etc. Many methodologies involve object-oriented programming. On this page, methodologies are arranged in three groups and levels: 1) Top: named methodologies. 2) Middle: types or classes of modeling languages used in development. 3) Bottom: specific modeling languages, with their own directory category.