User Analysis is concerned with determining those characteristics of the user that may make an impact on the design of the interface.
Task Analysis is concerned with determining those characteristics of the task that may make an impact on the design of the interface.
By "task", we mean the job/activity, and associated goals, that the user wishes to accomplish while using the interface.
The User Analysis and the Task Analysis together help set the requirements for, and constraints on, the interface design activity.
Neither User Analysis nor Task Analysis are about the interface directly.
All of your questions for User Analysis, should be about the
characteristics of the user. e.g., age, culture, personality,
education, handedness, other physical characteristics, etc.
All of your questions for Task Analysis, should be about the
characteristics of the task. e.g., actions, actors, objects,
frequencies, importance, grouping, decompositions, information
sources, results, communication, tools, likely errors, terminology,
relationships between tasks, etc.
In Task Analysis, focus on Task Objects and Task Actions. Start with trying to list the objects in the task. i.e., what needs to be used, created, destroyed. Then try to see what the basic task actions are. In the process of doing that you may find more objects.
The Task Analysis does not describe how a user would carry out the task using the interface. The interface has not yet been designed! The Task Analysis does allow you to build a conceptual model of the task.
It helps if you try to use a different vocabulary for the task than you use for the interface -- i.e., clearly separate task objects from computer objects. For example, an actual document versus an icon that looks like a sheet of paper. Make a lexicon for the conceptual model of the task (i.e., in the user's vocabulary). Later you can make a separate one for the terms used in, and about, the interface that you design. These lexicons help ensure consistency.
dcb at cs wpi edu / Tue Mar 7 19:55:30 EST 2006