AbstractConsidering as young countries those parts of the world which were occupied and to some extent populated as a result of "Europe's expansion", which began with the discovery of America and extended to Australia, New Zeeland and some parts of Africa, the author tries to make a distinction between two completely different types of colonies in accordance with the way these areas were colonized. In the "exploitation" type of colony, a small number of european immigrants were conquerors, governors, missionaries, landowners, lawyers, merchants, military or civil servants and belonged to a superiors class, whereas the natives were doing most of the actual work. In the "colonization" type, the native population, which was very scarce, has been dislodged and some cases exterminated and the work was done by the immigrants or imported slaves. Argentina, Uruguay, the South of Brazil and Chile belong to the "colonization" type as also most of the United States, Canada, Australia and New Zeeland, whereas most of the Latin- American republics were colonies of the "exploitation type". To-day these countries, especially those of English origin, enjoy a high income level, because the access to education and technical knowledge enabled the population to get the benefit of a high productivity. As to the countries of Spanish origin, before the second world war, Argentina and Uruguay had a per capita income very close to that of the English origin countries, but comparing with the year 1950, although Argentina is in a higher position than other Latin-American countries, her income level is lower than that of ten countries of Western Europe. One can say that the material living standard is generally higher in Argentina than in other Latin-American countries of the "exploitation" type, but lower than in the "colonization" type of British origin countries.