Since the times of August Compte and Karl Mannheim (but also since José Ortega Gasset and Antonio Gramsci), the generation concept has always been a relevant topic in social science and humanities. As a metaphor of social construction of time has been one of the most influential categories, not only in the theory debate, but also in the public sphere of youth investigation. Even though the uses and abuses that this concept has had are well established in the European context during the periods of both world wars, it has had importance in the ideality and political debates in other regions also. This article intends to retake the concept of generation from a historical perspective, highlighting its importance in the contemporary debates on youth.