The concept of "generation" is one of the most important and compelling in the sociology. This appeal has led individuals in other fields to discuss about generations as well. Given that understanding many concepts and ideas within the social sciences necessitates a grasp of their historical context, this article endeavors to analyze the concept of generation based on a five-stage periodization of sociology proposed by Johan Goudsblom and Johan Heilbron (2015): the pre-sociological period, the formation of sociology as an intellectual idea, the establishment of sociology as an academic discipline, the consolidation of the discipline within universities, and late sociology. This article is a narrative review that delves into the nature of the generation concept. Ultimately, by differentiating between sociological and demographic conceptions of generation, the article concludes that many discussions about generations deviate from the sociological understanding.