In this article I have tried to highlight the many criteria according to which tourism is classified and what are its main forms. Tourism is considered to be the most developed industry at the European level with a strong economic impact and the highest annual growth rate. Because of its scale and its various elements , but also because of the value and originality of these elements, tourism is the main motivation of all that is tourist traffic . A particular area or landmark is an interest to travel as far as that can provide tourist activity. The tourism potential of an area can be defined as all the elements that make up the sights with facilities to receive tourists representative. The main types of tourism that will be detailed in this article are: tourism, recreation and leisure, healthcare tourism, tourism or curative spa, cultural tourism, educational, social, or complex-type shopping tourism. The criteria according to which can be classified tourism are: distance, length of stay, geographic origin of tourists, type of transport used, how to organize your stay, the conduct of the stay, peculiarities destination, interaction travelers with the destination, the price paid, tourist`s age, the number of tourists. Depending on the area of origin, tourism and domestic tourism are classified in international tourism. Such, international tourism is classified in inbound tourism and outbound tourism. Any travel between these two forms is particular between which there is no definite boundary but some interdependence that helps promote tourism activities. Depending on the degree of mobility of tourists, tourism classified in tourism accommodation and tourism traffic. Tourism residence has three forms, namely long-stay tourism, tourism stay average stay lasting tourism and stay for a brief stay. Seasonality is another factor that affects tourist flows. This tourism classified into 3 types: winter tourism, summer and circumstance. Depending on the means of transport used distinguish the following forms of tourism: hiking, tourism, rail, road, sea and air. Tourism travel motivations of tourists divided in the following forms: leisure tourism, leisure and recreation, spa treatments or cures, sports, shopping, technical or scientific or religious. Specific forms of tourism based on the socioeconomic characteristics of the application are: tourism, particularly social tourism and business tourism or congresses. A particular form of social tourism is tourism for youth which is addressed to students, students or young people, usually with a educational purpose. Tourism forms are holidays for young people, educational tourism, international camps, Work and Travel, volunteer camps, or tourism practiced to learn some foreign language. Depending on the age tourists have youth tourism, for the active and the elderly.