What is the biggest industry in tourism?

The primary industry is agriculture, the secondary industry is industry, and the tertiary industry includes tourism, service industry and other industries except agriculture and industry.

Related introduction:

Tourism, called tourism industry internationally, is a comprehensive industry that attracts and receives tourists and provides transportation, tourism, accommodation, catering, shopping and entertainment. Tourism business should be composed of tourism, transportation and passenger accommodation represented by hotels. They are the three pillars of tourism.

Tourism is an industry that provides tourist services based on tourism resources and facilities. Also known as smokeless industry, invisible trade. In a narrow sense, tourism mainly refers to travel agencies, tourist hotels, travel companies and tourism specializing in tourism commodity trading.

In addition to the departments specializing in tourism business, tourism in a broad sense also includes all walks of life related to tourism. As a new type of advanced social consumption, tourism often organically combines material life consumption with cultural life consumption.