Biological hierarchy refers to the systemic organisation of organisms into levels, such as the Linnaean taxonomy (a biological classification set up by Carl Linnaeus). It organises living things in descending levels of complexity: kingdom, phylum, class, order, family, genus, and species.

The heirarchy of life describes the relationship between different organisms and is arranged based on complexity. The lower levels tend to represent atoms to higher levels which are biospheres.

The hierarchy of compound biological systems and structures, defining life with the help of the reductionist type of approach is termed as abiological organization. The biological organization extends from the atoms and goes till the biosphere. When you look at the higher levels of this organization, it is called the ecological organization.

Biological organisation is the organisation of complex biological structures and systems that define life using a reductionistic approach. The traditional hierarchy, as detailed below, extends from atoms to biospheres.

“Taxonomic hierarchy is the process of arranging various organisms into successive levels of the biological classification either in a decreasing or an increasing order from kingdom to species and vice versa.” Each of this level of the hierarchy is called the taxonomic category or rank.