In a world of open boundaries where the free circulation of spiritual assets and the impetuous flood of information is assured, it appears natural to attempt to assume the clarification of fundamental concepts regarding the art of sounds such as it has been the case in European countries or, to be more specific, in music composed during the 20th century. This stage that was formerly a privilege of a few centres, later of countries, has now been replaced. The united effort of generations has built an impressive thesaurus, generating patterns taken over by still crystallizing cultures which are, in their turn, creating their own musical patrimony whose powerful propensity needs to be inventoried and made available to other people.