This paper elaborates on the various scientific problems and difficulties regarding the notion of social type in the social sciences, particularly in sociology. An extensive body of literature on this topic is reviewed, and numerous ambiguous and vague points associated with this concept are identified. Some conceptual clarification and resolution is proposed to articulate the precise difference between social type and the concept of role. A typology of four major mechanisms or sources from which social types may emerge and be identified by sociologists is presented: occupational, psychological (inborn traits), cultural/,sub cultural, and mythological. Each source/mechanism forms a different, or slightly different, type of social type.