Booking.com provides a wide range of accommodations, from hotels to apartments, as well as flexible cancellation policies and detailed user evaluations, making it great for all types of tourists.

Trivago.com serves primarily a hotel price comparisons site, allowing guests to easily find the best rates across many booking platforms.

Hotels.com focuses on hotel bookings and rewards loyal customers with a program that grants one free night after every ten nights booked.

Expedia.com is a full-service travel site that allows customers to book hotels, flights, rental cars, and holiday packages, typically with discounts when services are bundled.

Kayak.com is a reliable travel search engine that combine offers from many different companies to provide options such as price tracker, flexible date searches, and organizing a trip.

To summarize everything, Booking.com and Expedia.com provide full travel services, Hotels.com is great for hotel-focused tourists, while Trivago and Kayak are ideal for people who want to compare prices and explore deals.