The laser is one of the most fantastic and versatile tools ever invented by men, and its story began long ago with the observation of many natural optical phenomena. However, the true nature of light started to emerge only in the 19th century, was completely understood at the beginning of the 20th century and, finally, in 1960 the various basic and technical knowledges coalesced for the realization of the first laser device. Since then the laser field exploded almost exponentially, and thousands of different materials, in the state of solids, liquids, vapors, gases, plasmas, and elementary particles have lased up to now from less than 1 Å to more than 1 mm. Lasers have been applied in various fields with such outstanding results that many practical aspects of human life cannot be fulfilled anymore without them. Moreover, the laser light has started an unprecedented revolution in optics because of its unique properties unrivaled by any other natural and artificial light source. In particular, it contributed to the development of new chemical and physical processes which, besides pervasive applications, have been used also to fabricate new photonic materials, with the notable consequence of advancing and enriching the laser field itself. In general, although a few sectors show signs of maturity, the laser field as a whole looks well and alive, and there will be a new golden age also as a consequence of impressive technological advances.