Economic Categories in Tax Relations System: Interconnection, Interdependence and Semantic Differences in the Nature of Concepts

The aim of this research is to study the essence, interrelation and interdependence of economic categories such as "tax system", "system of taxation", "tax mechanism," "taxation mechanism" in tax relations system. The study proved that a component of the tax system is the system of taxation. The tax system is a set of tax relations, built on the basis of the relevant principles, functions, elements and methods of taxation, based on the legislative consolidation of the combination of types and forms of taxes and duties established by the mechanism of calculation and payment (the mechanism of taxation), a specific order of administration and the activities of authorized state authorities and taxpayers to ensure full and timely receipt of taxes and duties to the budgets of different levels. The system of taxation is a combination of taxes and fees charged within the legally established procedure. Tax mechanism is a set of rules, tools and methods of organizational, legal and administrative nature which ensure the functioning and regulation of the tax system and focused on the implementation of state tax policy. Mechanism of taxation is a structural component of the tax mechanism, and its elements are the instruments of tax mechanism. The approaches to understanding the nature, content and interrelationship and interdependence of these categories have been proposed. These approaches are aimed at building rational tax relations that can stimulate the development of the national economy.