Final answer:
OTAs are integral to the tourism system, serving as major components that facilitate travel planning and bookings, contributing to tourism's status as a significant economic driver worldwide.
Step-by-step explanation:
Online travel agencies (OTAs) are indeed among the largest companies within the tourism system, deeply integrated into what is likely the world's largest industry. OTAs have transformed the way we book travel, offering convenience and accessibility to consumers while generating significant revenue. In the tourism system, they play a crucial role by aggregating flight, hotel, and other travel services, making it easier for tourists to plan and book their trips. Importantly, tourism is not only about leisure and holidays; it is a major economic driver in many areas. In places like India, the focus on unique natural environments and historical sites has made tourism a significant part of the economy. Similarly, Australia markets its diverse landscapes and urban experiences, to the benefit of its economic standing. Islands and remote locations, however, often struggle with the investment needed to build the infrastructure necessary to attract tourism. Nevertheless, different strategies are employed globally to appeal to tourists, from pristine beaches and warm weather to historical sites and natural wonders, all of which create a complex and vibrant tourism system.