Tourism is an economic phenomenon with important sociocultural implications that acquired a fundamental significance in the last decades of the twentieth century. It is one of the economic sectors with the highest rates of growth, together with transportation, communications, and the computer industry, with which it works in a synergitic way.

According to a classic definition, tourism can be identified in the complex of relations and manifestations that rise from the travel and stay of foreigners when the stay is temporary and is not motivated by a lucrative occupation (Hunziker and Krapf 1942). "Foreigners" are persons who do not reside habitually in the zone in which the tourist activity is carried out; depending on wether the zone of residence is in the same state, one can distinguish between internal tourism and international tourism.

Other elements have to be considered in distinguishing fully-fledged tourism from similar activities. First, two "fundamental...