This paper aims to produce a theoretical essay about the modern hotel from a historical and critical perspective, seeking to broaden knowledge about the mutation of this architectural typology in the context of the development of mass tourism, hypothesizing that hotels are "lodging machines". This is a conceptual discussion aimed at fostering and subsidizing the debate on hotels built between the late 1940s and the 1970s, in the context of the Modern Movement. To this end, he recalls the semantic and typological antecedents of the hotel and discusses how the social practices of mass tourism and the role of the state were reflected and reproduced in the mechanisms of modern hotels. Then, it presents aspects relating to the formal and functional typologies that support the idea that the modern hotel is a lodging machine, emphasizing some characteristics that express its architectural modernity. Finally, it highlights the historical and heritage relevance of modern hotels and the importance of documentation for intervention and conservation of this collection as material witnesses of modern architecture and mass tourism. Keywords: Hotel, Lodging Establishments, Modern Architecture, Mass Tourism, Architectural Typology.