Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


What the directory contains:

  • Readme.html: this file
  • WebVIP directory
  • VisVIP directory
  • FLUD directory 



Good usability is critical to the success of any website. The objective of the NIST Web Metrics project is to develop tools and techniques to facilitate evaluation of the usability of websites. The dynamic nature of the Web poses problems for usability evaluations. Development times are rapid and changes to websites occur frequently, often without a chance to re-evaluate the usability of the entire site. New advances in Web developments change user expectations and users are often scattered across the globe. To address how to incorporate usability evaluations into such an environment, we have adapted traditional user-centered design and usability testing methods in order to produce prototypes of tools that are rapid, remote and automated.

Why will you use these tools:

If you are using Methods #1 or #2 referred to in the Overview, you will NOT use these tools. Methods #3 uses the tools as described briefly below. WebVIP has been used to produce the instrumented website (TMFsite_instrumented). Javascript fragments have been inserted into the pages of the website that allow the automatic capture of user interactions, such as keypresses, mouse clicks, and entering and leaving windows. WebVIP may also be used to perform a custom instrumentation of a website so that more or fewer events can be captured. See the documentation at WebVIP/Readme.html for more detailed information.

FLUD (Framework for Logging Usability Data) is the format for the interaction data. You do not need to understand more about FLUD unless you intend to develop your own tools. Information about the format is provided in FLUD/draft-format.html.

The logs written by WebVIP during your users' sessions can be post-processed so that you can view a 'pretty-print' version. These logs can also be used for the VisVIP visualization. See VisVIP/Readme.html for more information.

For more information:

See the NIST Web Metrics website at:



<Return to the CIFter Home Page>


Created September 29, 2016, Updated October 19, 2016