Tourism as the world's largest industry Tourism is a typical fashion activity in which the public participates extensively and its importance has grown over the of recorded human history. Countless articles refer to tourism as “the largest industry in the world”; politicians, analysts and scholars often talk about the size of tourism compared to other sectors (Smith 2004: 26). This series of misleading statements, together with mass media reports (out of context), create the idea that tourism is one large industry imprinted in the minds of many people. However, in this essay I will demonstrate that this is a simplistic and misleading idea, which should be replaced with the plural term “tourism industries”. Furthermore, tourism is not the largest industry in the world, but the largest service sector. Is tourism an industry and, if not, what is it and how can it be defined? To answer these questions we must first find the definition of industry. An industry is a group of companies that produce products and/or services that are closely substitutes for each other (……). To be considered an industry, it must satisfy three factors: individual businesses, revenues of those businesses, and a common product. Now let's see what tourism is. However, there is no single definition, i.e. no agreement on what tourism should be. There are a few reasons: tourism includes a number of different sectors (e.g. transport, accommodation, attractions, other services); tourism encompasses a number of academic subjects: some argue that tourism is conceptually weak as a subject; difficult to establish rigid boundaries around tourism both as a business and as an area of ​​academic study; weak data sources that make cross-country comparisons difficult.