A map of world regions. Source: U.S. Department of Defense.

Regions are artificial constructs that geographers use to divide the world into sections which can then be compared with other units or studied in more detail on their own. Their defining feature is that the phenomena being studied exists in greater concentration within the boundaries than it or they do outside of it. We have been made familiar with their use since grade school when we were first introduced to a map of the world with the continents or the seven seas labled. But regions can be as large as a hemisphere or as small as a city block. As scholars progress in their study of the discipline, they utilize more specific and complex types of regions to understand spacial relationships. Rather than size, it is the criteria chosen that establishes the boundaries. There are several different kinds of regions.

1. Formal (also referred to as uniform regions)
2. Functional
   1. Nodal
   2. Network
3. Vernacular

Formal regions are frequently used to outline governmental, physical, cultural and economic areas. Some familiar examples include, Canada, the Rocky Mountains, the Islamic World, or the rice-growing areas. Functional regions are frequently used for service areas, for example, areas served by a particular utility company. Nodal regions are a particular type of functional region that is defined by the point-to-point nature of activity. For example if we wanted to identify places in the United States that have a certain number of telephone calls placed to London over a given period of time, these locations would be represented by points on a map, rather than a particular contiguous area. Network regions describe networks of activity—for example, delivery routes.

Vernacular regions are constructed by peoples' perception and therefore vary in extent from person to person. They exist because people refer to them as if they are real. Perfect examples are provided by the terms Midwest, Dixie, and Down East. If you gave people maps of the United States and asked them to drawn a line around any of these regions their boundaries would vary considerably.