Taxonomy has always been a controversial field of biology because it is interlinked with other biological areas, and also requires a philosophy. Currently, four main schools are practising taxonomy. These are traditional taxonomy, phenetics, evolutionary taxonomy and cladistics. Each one has different approaches either in their philosophy or methodology. The task, here, is not to argue which one is superior or to recommend one for usage. Instead, we attempt to give a short introductory review on cladistics which has been widely practised in the last three decades.