This document provides an introduction to tourism, including definitions, components, and costs and benefits. It defines tourism from the perspectives of tourists, businesses, governments, and host communities. Tourism is defined by the UNWTO as activities of people traveling outside their usual environment for less than a year. It discusses different types of tourism (international, domestic, etc.) and classifications of visitors. The key components of tourism include tourists, the environment, infrastructure, and the various sectors of the industry. Benefits include jobs, income, and infrastructure, while costs include environmental and social impacts.