According to Smith (1988), author of a specialized dictionary on tourism, the word "tourist" was introduced in 1800 and the word "tourism" in 1811. However, what exactly is " tourism"? Who are the "tourists"? Researchers and practitioners have produced many definitions for both “tourist” and “tourism,” but no definition of either term has been widely recognized, regardless of the fact that both terms have now been part of the English language for over two centuries. As indicated by Smith (1988), he suggests that “there will probably never be a single definition of tourism” or tourists as economists, psychologists and geographers perceive different things about tourism in their professional fields (Smith 1988 cited in Leiper 1995: 3). However, any approach to defining both terms is highly constructive as it provides us with greater 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). After discussing "tourism", the focus then shifts to "tourists" where, once again, Stear (2005), Leiper (1979) and Weaver and Lawton (2006), define "tourists" illustrating how each definition are different from each other. One of the first attempts to define tourism was that of two Swiss academics, Professors Hunziker and Krapf of the University of Bern. They defined tourism in a 1942 study as a complex of environmental impacts: "the set of phenomena and relationships deriving from the travel and stay of non-residents, as they do not lead to permanent residence and are not connected to any activity of I earn". This definition has been recognized by many international associations including...... middle of paper ......ry' in Annals of Tourism Research Oct/Dec '79, School of Business and Administrative 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 Clearly Conceptualizing 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L. and Wixon, D. , (2007), 'Some heuristic definitions for the study of highly industrialized tourism systems', unpublished monograph, School of Leisure Sport and Tourism, University of Technology, Sydney.Weaver, D. and Lawton, L. (2010), ' Tourism Management' 4th Edition, John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.