No, KAYAK is not the same as Expedia. The key difference is KAYAK is a metasearch engine while Expedia is an online travel agency. KAYAK allows you to compare travel prices across airline, hotel, car rental, and other booking sites. But KAYAK itself does not sell or book travel. Expedia owns its travel inventory and allows booking directly on their website. So KAYAK helps find the best deals but you need to book elsewhere. Expedia consolidates search and booking in one place but may not have the lowest prices on every flight or hotel. KAYAK partners with Expedia and other major booking sites. You may end up purchasing travel through Expedia after searching on KAYAK. But the two sites are fundamentally different.