Acting under the directive of the leadership of the 104th Congress to make Federal legislative information freely available to the Internet public, a Library of Congress team brought the THOMAS World Wide Web system online in January 1995, at the inception of the 104th Congress. Searching capabilities in THOMAS were built on the InQuery information retrieval system, developed by the Center for Intelligent Information Retrieval based at the University of Massachusetts at Amherst.
The first database made available was Bill Text, followed shortly by Congressional Record Text, Bill Summary & Status, Hot Bills (no longer maintained), the Congressional Record Index, and the Constitution (now found, along with other historical Congressional documents, under the "Historical Documents" category on the THOMAS home page). Enhancements in the types of legislative data available, as well as in search and display capabilities, have been continuously added.
New files are indexed and made available for searching as soon as they are received from the Government Printing Office (GPO). The bill text files are updated several times throughout the day. The Congressional Record files are updated once a day, when Congress is in session, usually in the morning. Committee reports arrive intermittently, after they are published by GPO, and are indexed when they arrive.