Community
A community is a small or large social unit (a group of living things) who have something in common, such as norms, religion, values, or identity. Communities often share a sense of place that is situated in a given geographical area (e.g. a country, village, town, or neighborhood) or in virtual space through communication platforms. Durable relations that extend beyond immediate genealogical ties also define a sense of community. People tend to define those social ties as important to their identity, practice, and roles in social institutions like family, home, work, government, society, or humanity, at large. Although communities are usually small relative to personal social ties (micro-level), "community" may also refer to large group affiliations (or macro-level), such as national communities, international communities, and virtual communities.
Public
In public relations and communication science, publics are groups of individual people, and the public (a.k.a. the general public) is the totality of such groupings. This is a different concept to the sociological concept of the Öffentlichkeit or public sphere. The concept of a public has also been defined in political science, psychology, marketing, and advertising. In public relations and communication science, it is one of the more ambiguous concepts in the field. Although it has definitions in the theory of the field that have been formulated from the early 20th century onwards, it has suffered in more recent years from being blurred, as a result of conflation of the idea of a public with the notions of audience, market segment, community, constituency, and stakeholder.