Package plan.

Many airlines now offer customers the opportunity to book hotel rooms through their Web sites. Is there an advantage to doing this over just booking my hotel room separately? Who am I really getting my hotel room from?

This is a fairly new feature on airline-run booking sites but something that has been offered for some time at more general online travel sites such as Yahoo! Travel and Travelocity. As far as airlines go, the answers to all these questions really depend on what airline you fly. Delta, for instance, simply connects you to another company that specializes in hotel bookings. "Delta offers a partnership with Hotels.com. We transfer you directly to a Hotels.com representative and they take up the booking process for the hotel," says Delta spokeswoman Gina Laughlin. "Hotels.com has large access to multiple hotels and is known for lower prices." The only advantage here is that you can get all your basic vacation needs at one convenient stop without having to dial various numbers.

At American Airlines' site, things are a little different. Unlike Delta, where Hotels.com acts as the booking agent, American becomes an agent for the hotel, allowing customers to book the rooms directly through the airline instead of having to deal with another agent. Billy Sanez, a spokesman for the airline, says that American has been doing this for several years. It also offers vacation packages, which can include hotel stay, air tickets and land transportation. As with Delta, an advantage in American is one-stop shopping. There is the added bonus of not having to pay booking fees, which other online travel portals charge. "We can showcase companies that give miles through hotels and car bookings, which is something our customers really want," Sanez says. American's plan allows fliers to accumulate more loyalty miles, which they can use later. Another advantage is that customers with AAdvantage miles can use those to purchase vacation packages or individual hotel or car tickets.

TAM Airlines offers packages similar to the ones found at American Airlines, but only for customers in Brazil. As far as hotels go, the airline recommends that its passengers contact a travel agent to book the flight and hotel room at the same time. The best thing to do if you are considering booking a hotel room through your airline is to ask about the details. Since not all airlines are on the same page about this issue, there's often no way to know exactly what kind of deal you're getting.