Numerical taxonomy is aclassification system in biologicalsystematics which deals with the grouping bynumerical methods oftaxonomic units based on their character states.[1] It aims to create ataxonomy using numeric algorithms likecluster analysis rather than using subjective evaluation of their properties. The concept was first developed byRobert R. Sokal andPeter H. A. Sneath in 1963[2] and later elaborated by the same authors.[3] They divided the field intophenetics in which classifications are formed based on the patterns of overall similarities andcladistics in which classifications are based on the branching patterns of the estimated evolutionary history of the taxa.In recent years many authors treat numerical taxonomy and phenetics as synonyms despite the distinctions made by those authors.[citation needed]
Although intended as an objective method, in practice the choice and implicit or explicitweighting of characteristics is influenced by available data and research interests of the investigator. What was made objective was the introduction of explicit steps to be used to createdendrograms andcladograms using numerical methods rather than subjective synthesis of data.