The introduction and establishment of a unified metric system was an important step towards the organization of human society. By the term “metric system” we mean a series of units for measuring length, surface, volume, capacity, weight and currency efficient in serving the demands of all activities of a society. The metric system has facilitated the various transactions, programming and organization and is a fundamental priority for any scientific development. This article is not the product of systematic research into the characteristics and qualities of different metric systems. It has at its aim to explain certain problematics related to research on land registry measurements. Therefore, it only refers to metric details related to the measurement of such surfaces. The study has been articulated in two parts. The first deals with some general concepts of the metric system in itself and classifies the surface metric units according to their base. The second part presents a concise description and brief commentary on the main systems known to us, which are related to or have influenced the metric system used on Greek territory.