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The FLUD format: Logging Usability Data from Web-based Applications



John V. Cugini


This paper presents a proposed format for representing the behavior of users as they interact with a Web-based application. The captured log data can be valuable for analyzing and improving the usability of such applications. The background and motivation of this effort are briefly described. The detailed syntax and semantics of the format are then defined.
Special Publication (NIST SP) - 500-247
Report Number


logging data, usability testing, web-based applications


Cugini, J. (2001), The FLUD format: Logging Usability Data from Web-based Applications, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 19, 2024)


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Created January 24, 2001, Updated May 9, 2012