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What the directory contains:



The Framework for Logging Usability Data (FLUD) format has been developed to support and encourage sharing of usability data. By standardizing the way in which user interactions are captured, it becomes to possible to develop tools that can be shared.

When this tool is used:

If you decide to use a WebVIP-instrumented version of the TMF website, whether it is the one provided in the TMFsite_instrumented directory or one that you create yourself with the customization option, the resulting user log files will be written in FLUD notation.


  • FLUD output will be automatically generated when your subjects perform tasks with a WebVIP-instrumented website.
  • To convert the FLUD output to formats that can assist the usability engineer in understanding the subjects' interaction patterns, you will need to email the logs to NIST, as described in WebVIP/Readme.html 

For more information:

The full description of the FLUD format can be found at: draft-format.html


The FLUD format is a research product developed at the National Institute of Standards and Technology by employees of the Federal Government in the course of their official duties. Pursuant to title 17 Section 105 of the United States Code this format is not subject to copyright protection and is in the public domain.

FLUD is a research prototype. As you might imagine, NIST assumes no responsibility whatsoever for its use by other parties, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic. 

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Created September 29, 2016, Updated October 19, 2016