(Dialog, A Thomson Corporation business, Cary, NC, www.dialog.com). The first commercial online information retrieval system, created by Roger Summit in 1967 and launched as a service in 1972. For years, DIALOG has offered the largest single collection of information available online, claiming over 900 databases in areas such as business, science, finance and law. Searching is free, but there are fees for viewing the results. Access is available via the Web or by separate dial-up numbers as was the norm before the Internet became popular. DIALOG's searchable content is considered to be part of the deep Web.