Travel agencies, as defined by the World Tourism Organization, are "retail agencies that provide information to the public about possible travel, residence and related services, including remuneration and conditions for services". Travel organizers or production wholesalers or wholesalers prepare for travel and residence by organizing transportation, booking different accommodations and offering all other services before the demand for travel is put forward. Industrial institutions. China's "Regulations on the Administration of Travel Agencies" pointed out that: travel agencies refer to enterprises engaged in tourism business for the purpose of making profits. Among them, tourism business refers to the business activities of providing paid services for tourists such as outbound, entry and visa procedures, attracting and receiving tourists, and arranging accommodation and meals for tourists. Travel agency's operating items usually include the sale of various transport tickets (such as air tickets, bus tickets and ship tickets), package itineraries, travel insurance, travel books, etc., and consulting agents for certificates (such as passports and visas) required for international travel. The smallest travel agency may have only one person, while the largest travel agency has branches all over the world. Careers derived from travel agencies include: leader, tour guide, ticket clerk, visa commissioner, adjuster (tourist operation), etc. To operate a travel agency, it is necessary to hold a valid license issued by the authorities, and must be a member of the Chamber of Commerce of a designated travel agency in order to operate a travel group and conduct a group tour.