KAYAK, founded in Jan 2004, is an online travel site that helps to compare hundreds of travel sites at once. It gives choices where to book, including airline, hotel, car hire and online travel agency sites.
They will send user right to the booking page to finish their purchase. User can also book hotel or hire car right on KAYAK.
KAYAK Mobile is a mobile App for almost every platform to find best deal on flight or hotel. KAYAK also offers travel management tools to manage your itinerary, check your flight status and get price alerts.