What is the science of organizing categories for living things?

The science of organizing categories for living things is called taxonomy. Taxonomy is a branch of biology that deals with the identification, naming, and classification of living things. It is a hierarchical system that arranges living things into different groups based on their similarities and differences. The highest level of the taxonomic hierarchy is the domain, followed by kingdom, phylum, class, order, family, genus, and species. Each level of the hierarchy is more specific than the one above it. For example, there are only three domains (Bacteria, Archaea, and Eukarya), but there are thousands of species. Taxonomists use a variety of tools to identify and classify living things, including morphology, genetics, and behavior.