The subject of classification is taken into account to be monotonous by the majority. Classification systems help to assemble similar disease phenotypes in more homogeneous syndromes. Over the years, various researchers have done extensive work in the development of classification of periodontal diseases. Though we have made great strides towards the understanding of periodontitis in general, the bitter truth is that we have not hit the bull's eye on the true nature of etiopathogenesis. Until then any classification based on infectious etiology would be a misfit. A classification that is easy to understand and based on treatment needs would be more apt at this juncture. This article is aimed at discussing the American Academy of Periodontology 1999 and present 2017 the World Workshop Classification Systems to know and simplified the modifications.