The purpose of this article is to describe the impact exerted by the main variables that are part of the economic activity, so that can be understood easily, the origin, behavior, trends and cause-effect relationship, the concatenated variables with economic and social growth. The development of this article is based on the analysis of the behavior of economic agents such as Family, Government, Business and External Sector, and the factors shaping the characteristics of each one of them as the Consumer Savings, Taxes, Income available, Investment, Public expenditure and Interest rate market, among other no less important. This article is the result of the author's experiences for many years as an observer in the field of economy, and as a university lecturer, therefore although aspires not exhaust the subject, will serve as illustration and consultation for both students and for people interested in this important topic. The writing is reflective, analytical, historical and descriptive, considering that historical data will be analyzed, will be processed through thoughtful analysis, and then the reader will be presented descriptively.