AT&T Corp announced a service to enable businesses to build and maintain sites on the Web and attract customers to the site. It also said it would guarantee credit card transaction security for those who shop on the Web and charge their Internet purchases to their AT&T Universal credit cards. AT&T said its offer was aimed at both consumers and merchants. It also said merchants buying its Secure Buy service would not miss an order; it would refund the value, up to the monthly Secure Buy service fee of $395 to $595 a month, if an order does not reach a merchant.