One place may also differ from another in the ideologies and philosophical or religious tenets of people who live there, by their languages, and by their forms of economic, social, and political organization. People modify and adapt to natural settings in ways that reveal cultural values, economic and political circumstances, and technological abilities. It is important to understand how such human-environment relationships develop and what the consequences are for people and for the environment. The most visible evidences of global interdependence and the interaction of places are transportation and communication networks linking every part of the world. These demonstrate that most people interact with other places almost every day of their lives.
Interaction continues to change as transportation and communication technologies change.
We need to anticipate these changes and to examine their geographical and societal consequences. The basic unit of geographic study is the region. The region is any area that displays unity in terms of selected criteria. We commonly use regions to show the extent of political power, such as nations, provinces, countries, or cities. However, there are almost countless ways to define meaningful regions, depending on the issues and problems being considered.