THE VERSATILITY AND ADVANTAGES OF USING ON-LINE INTERACTIVE DISPLAYS ARE ILLUSTRATED BY EXAMPLES FROM (1) THE GENERAL PURPOSE DISPLAY SYSTEM (GPDS), (2) THE PATTERN LEARNING PARSER (PLP II), AND (3) THE BIBLIOGRAPHIC ON-LINE DISPLAY SYSTEM (BOLD). ALTHOUGH THESE SYSTEMS ARE DESIGNED FOR DIFFERENT PURPOSES THEY ALL UTILIZE DISPLAYS AS COMMUNICATION CHANNELS BY WHICH THE MAN AND THE MACHINE ARE ABLE TO ENGAGE IN A DIALOG AND WORK TOGETHER TO SOLVE PROBLEMS. THE COMPUTER PROCESSES DATA RAPIDLY AND DISPLAYS THE RESULTS. THE INFORMATION PROVIDED IN THE DISPLAYS ENABLES THE USER TO STEER AND CONTROL THE STEP-BY-STEP PROGRESS OF THE PROGRAM. THIS PAPER WAS DELIVERED AT THE CONGRESS ON INFORMATION SYSTEM SCIENCE AND TECHNOLOGY (3RD, BUCK HILL FALLS, PENNSYLVANIA, NOVEMBER 20-23, 1966). IT IS AVAILABLE AS AD-640-652 FROM THE CLEARINGHOUSE FOR FEDERAL SCIENTIFIC AND TECHNICAL INFORMATION, SPRINGFIELD, VIRGINIA 22151, $3.00 FOR HARD COPY, $0.65 FOR MICROFICHE, 35 PAGES. (AUTHOR/CM)