According to Smith (1988), author of a specialized dictionary on tourism, the word "tourist" was introduced in 1800 and the word "tourism" in 1811. But what is it exactly? is “tourism”? Who are the “tourists”? Researchers and practitioners have produced numerous definitions of "tourist" and "tourism", but no definition of either term is widely recognized, even though both terms have become part of the English language for more than two centuries. As Smith (1988) states, he suggests that there "will probably never be a single definition of tourism" or tourists since economists, psychologists and geographers perceive different things about tourism in their own fields. professional (Smith 1988 cited in Leiper 1995: 3). However, any approach to defining both terms is very constructive as it gives us more knowledge and understanding of each term. In this essay, the different concepts of tourism are defined by academic authors such as Krapf and Hunziker (1942), McIntosh and Goeldner (1977) and Stear (2005). Having discussed "tourism", attention then shifts to "tourists" where once again, Stear (2005), Leiper (1979) and Weaver and Lawton (2006) define "tourist" while illustrating how each definition is different from each other. One of the first attempts to define tourism was by two Swiss academics, Professors Hunziker and Krapf of the University of Bern. They defined tourism in a 1942 study as a set of environmental impacts: "the sum of phenomena and relationships born from the travel and stay of non-residents, to the extent that they do not lead to permanent residence and do not are linked to no remunerative activity. » This definition has been recognized by many international associations, notably in the middle of the article ......ry' in Annals of Tourism Research October/December '79, School of Business and Administration Studies, Sydney Technical College, Australia . pp 390 – 407.Leiper, N., (1995), 'Tourism Management' Tafe Publications, Collingwood, Victoria. Reindrawati, DY, (publication date unknown), 'The difficult but interesting problems of a clear conceptualization of tourism and the tourism industry, and differentiating the two', Dosen Program Studi DIII Pariwisata FISIP Unair, Surabaya. Smith, SLJ, (1995), “Tourism Analysis – A Handbook”, 2nd edition, Longman Group Limited, Malaysia. Stear, L. and Wixon, D., (2007), “Some heuristic definitions for the study of highly industrialized tourism systems”, unpublished monograph, School of Leisure Sport and Tourism, University of Technology, Sydney. Weaver, D. and Lawton, L. (2010), “Tourism Management”, 4th Edition, John Wiley & Sons Australia.