DIALOG was the first interactive, online search system to address large databases while allowing iterative refinement of results. It was developed at Lockheed Palo Alto Research Laboratory in 1966, extended through contracts with NASA, and offered commercially in 1972. Its speed, ease of use, and wide range of data content attracted professional users worldwide, including scientists, attorneys, educators, and librarians. DIALOG preceded major Internet search tools by more than two decades.
