An example of Gemeinschaft is the Amish, while an example of Gesellschaft is a nation-state. The sociological categories were first proposed by Ferdinand Tönnies and describe the differences in social relations in a "society" (Gesellschaft) versus a "community" (Gemeinschaft).
According to Tönnies' original conceptual formulation, people in Gemeinschaften (communities) feel a sense of obligation or loyalty to the common group, more so than to themselves. Their activities are regulated by an inherent sense of the common good. Tönnies' ideal expression of Gemeinschaft was the family.
Gesellschaften (societies) contrast with Gemeinschaften because the larger association never takes precedence over the individual's self-interest. Rather, Gesellschaften are maintained through individuals acting in their own self-interest. A modern business is an example of Gesellschaften. German corporations are often called "Gesellschaft".