NEW YORK — Budget air carriers have been snatching up travelers and market share from troubled legacy carriers for the better part of two decades, and now they're whipping them on the Internet, too.
Airline Web sites have improved dramatically since the early days of the World Wide Web. They have shrunk the number of steps it takes to buy a ticket, made directions clearer and no longer require customers to create an account before they can make a purchase.
But industry observers and Web designers say the major network carriers are falling behind their low-cost rivals in producing dynamic, easy-to-use sites that help establish customer loyalty. That's a problem because the number of business and leisure travelers using the Internet to find and book airfare has grown substantially.
"The airline industry has certainly gone through a transformation in the Internet age, from having sole travel agents to taking matters in their own hands, to losing it to aggregation sites and winning them back," said William Rice, president of the Web Marketing Association.
According to Google Trends, which collects e-commerce data, the Internet is the No. 1 source for business and leisure travel. About 83 percent of personal travelers use it, as well as about 77 percent of business travelers, superseding traditional booking systems, such as Sabre or Galileo, which have been in service since at least the early 1970s.
And with business travel down significantly for the year, having a good Web site can make a difference in getting extra seats filled with the do-it-yourself leisure shopper.
Usability and transparency, said Web designers and observers, are key to attracting customers and selling more tickets.
"It's all about the purchase and the fewest steps as possible," said Paula Selvidge, a software-interface designer and a vice president at software maker PerfectForms.
Web sites with bold colors, clean lines and as little clutter as possible score highest for usability, Selvidge said.
Usability is the No. 1 killer of all online transactions, said Joseph Knecht, the managing director of the Web services firm Vipa Solutions. People drop off from a Web site when directions are unclear or if they are not finding what they want.