The User Action Notation &
Last Revision: 5 January 1997
The User Action Notation is a semi-formal task description
language. It is used to describe user-computer tasks for the a
variety of purposes, including:
- recording a design
- carrying out analytic evaluation of usability
- for writing user manuals.
Aims of this ATOM
This ATOM is intended to provide you with practise in writing UAN
task descriptions and experience in doing analytic evaluation of user
interfaces by means of a cognitive walkthrough.
At the end of the ATOM, you will
- be able to write a UAN task description of a small-scale
- using this task embedded in a scenario, perform a cognitive
- based on the cognitive walkthrough, identify simple potential
usability problems with the task.
- You should have an introductory familiarity with UAN. You may
have achieved this via attending lectures on your HCI course.
Alternatively, you can:
- read Chapters 5 -7 of Hix and Hartson, Developing User
Interfaces, Wiley, 1993. This is the most comprehensive account
of the UAN, built around an extended example.
- check out one of the web resources on the UAN, such as
at the University of Toronto.
- You will also need to know how to perform a cognitive
walkthrough. Information about the cognitive walkthrough technique
What You Must Do
- Read the
- Develop a UAN task description of the task described in the
scenario. Your description should have at least two subtasks
subordinate to the main task.
- Perform a cognitive walkthrough using your task description.
- Write up the results of your cognitive walkthrough,
identifying the major usability problems you have uncovered in the
- Submit your UAN task description and the results of your
cognitive walkthrough, using the submission procedure specified
How You Should Submit Your Work
Put your submission on a set of web pages. Email the URL of the
root page to:
The submission is due (i.e., the email must be sent) by 2pm,
Wednesday 11 February.
Comments on your submission will be supplied via the ATOM
co-ordinator. Your course tutor may organise a discussion of the
results or may ask you to supply further feedback. Consult your
course tutor if you are not sure what is expected of you.
The exercise used in this ATOM was developed by
Author: Philip Gray
Date of last revision: 5 January 1997