There are a number of benefits of tourism for both the tourist and the host destination. On a large scale it offers a good alternative to some more destructive industries for generating income both on nationally and privately.
The tourism industry encompasses many different areas, so it also creates jobs in many different areas. With tourism comes hotels, resturants, car rental agencies, tour companies, service stations, souvenier shops, sports equipment rentals, and much more. All of this creates many different levels of employment for people in a given community.
In many places the introduction and development of tourism allows local people an opportunity for economic and educational growth that would not otherwise be available. In addition, it allows both the tourist and the local community a chance to experience other cultures, which broadens understanding.
If properly used, tourism generated income can be tremendously beneficial to the host country and it's local communities. Tourism generated income can be used on a national and local level to better education, improve infrastructure, to fund conservation efforts, and to promote more responsible tourism.