KAYAK filed to go public in late 2010, then waited until 2012 to list. A few months after it finally did, Priceline agreed to buy it. The product searched travel sites so travelers did not have to. A single query showed flights, hotels and rental cars from airlines, booking sites and hotel chains side by side. KAYAK earned money from ads and when users clicked through to book. It was one of the best known travel brands online.

Staying Out of Booking

Steve Hafner and Paul English founded KAYAK in 2004. Both had earlier worked on travel and consumer sites. They believed travel shopping was too slow and scattered, and that clean, fast search would win. Their bet was to stay a search engine and leave the booking to others, which kept KAYAK neutral among sellers. Its clean design drew many loyal users.

Public for a Few Months

KAYAK priced at $26 a share in July 2012 and rose on its first day. Only a few months later, Priceline agreed to buy the company for about $1.8 billion. The deal closed in 2013. KAYAK continued as a separate brand inside Priceline, now Booking Holdings. Steve Hafner stayed on to lead it for years after the sale. Travelers still use KAYAK to compare prices.

Cover: A Fisherman Drinking Beside His Canoe, Paul Gauguin. Art Institute of Chicago, public domain. Chosen for a fisherman beside his canoe.