A population is all the organisms of the same group or species, which live in a particular geographical area, and have the capability of interbreeding. The area that is used to define a sexual population is defined as the area where inter-breeding is potentially possible between any pair within the area, and where the probability of interbreeding is greater than the probability of cross-breeding with individuals from other areas.
In sociology, a population refers to a collection of humans. Demography is a social science which entails the statistical study of human populations. This article refers mainly to the human population.