What is Kingdom?
Kingdom is the second highest taxonomic rank, just below domain. Prefixes can be added in order to create a subkingdom and a infra kingdom, two ranks below kingdom which are them divided into phyla. When Linnaeus began his foundations for kingdoms he divided them into two parts: the animal kingdom or Regnum Animale and the vegetable kingdom or Regnum Vegetabile. He late included minerals into the classification as Regnum Lapideum. Today there is no consensus as to how many kingdoms there are.