Pension as one of the most important categories of social security law requires an adequate, scientifically based and practically applicable sectoral conceptual reflection. To this end, the article attempts, taking into account the points of view common in the industry doctrine, to fix the fundamental properties of the considered kinds of social security provision and give them a meaningful legal description. The author uses a combination of methods of system-structural and applied system analysis as a methodological basis for describing the essence of pension.