This module describes the category and classification of plants and their relatives. There are five kingdoms in classification system. These are Monera, Protista, Fungi, Plants and Animals. The invisible Kingdom included Virus. Eukaryotic microorganisms possess membrane-bound cell organelles and include Plants, Fungi and Protists, whereas prokaryotic microorganisms possess lacking membrane-bound organelles and include Eubacteria and Archaebacteria.