What is the three domain classification system?

The three-domain classification system is a hierarchical framework that categorizes all living organisms into three primary domains based on genetic and molecular data. Introduced by Carl Woese in 1990, this system utilizes the sequences of ribosomal RNA genes to determine evolutionary relationships. The three domains are: Archaea, Bacteria, and Eukarya. This system replaced the previous five-kingdom model, offering a more accurate depiction of the evolutionary divergence of life forms.