Britannica Educational Publishing 
Economics and Economic Systems [PDF ebook] 

Although individuals and countries, for centuries, have exchanged goods and services for money, the formal field of economics-the study of wealth and how it is produced and distributed-is relatively young. Since Adam Smith’s pioneering work in the 18th century, economics has developed a great deal, and with it, so has our understanding of market systems, such as capitalism and centrally planned systems. A detailed explanation of the scope of economics, historical development, and the strengths and weaknesses of various economic systems is provided.