In 1758, Cox & Kings became the first travel agency in modern history. In 1840, the Abreu Agency was established in Porto by Bernardo Abreu, becoming the world's first agency to open its services to the public. A Thomas Cook travel agency in the United Kingdom, which ceased operating in 2019.

A tour operator controls, books and devises the whole trip. They create a package holiday by combining all elements such as hotel, airport transfers, activities, restaurants, tours and such like. A tour may not include all of these elements, the list is purely an example.

Travel agencies often offer a variety of services to their customers, including booking flights, rental cars, and hotel accommodations. They may also assist with planning itineraries, making recommendations for activities and excursions, and providing travel insurance.