The author's goal is to explain briefly and simply how the modern economy as a whole functions. This is achieved through the presentation of short and self-contained chapters that accurately and understandably present the terminology, developments, and structure of the economy. It fills a gap that exists between simple journalistic reporting of economic events and academic texts that are quite specialized for the public. It is aimed at a) those who have knowledge of economics, with the purpose of serving as a reference manual to which they can refer to recall anything related to the specific terms of microeconomics and macroeconomics, and b) those who have no training in economics, in order to explain economic concepts without being tiring.