2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/84171A hundred years ago, the quantum concept provoked a revolution in science and the search of a new conceptual basis for whole physics, as emphasized by Einstein. In this paper, I discuss the essential features of Planck's works in 1900 on the blackbody radiation and the hypothesis of energy quantization.Text in Portuguese, 13 pages, 5 figuresHistory and Philosophy of PhysicsPhysics Educationtext