The original concept of resource partitioning refers to the evolutionary adaptation of species as a response to the evolutionary pressure of interspecific competition. The more common basic biological usage is based on the different use of species in a particular niche for resources, rather than the specific evolutionary origins of these differences. This article explores the latter convention. When organisms compete for limited resources, there are two main types of competition: intra-species and inter-species. As indicated by the prefix, intraspecific competition refers to the competition of individual organisms of the same species for limited resources, while interspecific competition refers to the competition of individuals of different species for limited resources. When species compete for the same resources, a species usually has an advantage, even if it is only slightly. The perfect competition maxim indicates that perfect competitors cannot coexist. Species with advantages will exist for a long time. Weak species are either extinct or converted to occupy different niches.