It is common to find in textbooks the classification of living organisms into five kingdoms: Kingdom Monera, Kingdom Protista, Kingdom Fungi, Kingdom Plantae and Kingdom Animalia. It is now known that this classification has some serious flaws and that some kingdoms are no longer considered.
A widely accepted classification today is one that comprises one category above the kingdoms: domains. This classification was proposed by Carl Woese in 1977 and is based on molecular phylogeny data. According to Woese, there are three domains: Archaea Domain, Bacteria Domain, and Eukarya Domain.
