11.   Other carriers give extra frequent flier points for booking through their Web sites and offer discounts aimed at specific markets or regions.

12.   Some, called SilverPasses, offer discounts for two adults traveling together.

13.   For example, businesses could use data to customize advertising or offer discounts if consumers agree to allow personal information to be accessed by companies, Doty said.

14.   IDC Solutions Inc., an IDC unit, will also buy subscriptions from the two companies and offer discounts to IDC users, an IDC spokesman said.

15.   Retailers complain of having to launch sales or offer discounts to keep the merchandise moving.