TOG AND INTERFACES
First Principles of Interaction Design
Effective interfaces are visually apparent and forgiving, instilling in their users a sense of
control. Users quickly see the breadth of their options, grasp how to achieve their goals,
and do their work.
Effective interfaces do not concern the user with the inner workings of the system. Work
is carefully and continuously saved, with full option for the user to undo any activity at
Effective applications and services perform a maximum of work, while requiring a
minimum of information from users.This work is copyright 2003 by Bruce Tognazzini.
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Applications should attempt to anticipate the user’s wants and needs. Do not expect users
to search for or gather information or evoke necessary tools. Bring to the user all the
information and tools needed for each step of the process.
The computer, the interface, and the task environment all "belong" to the user, but
user-autonomy doesn’t mean we abandon rules.
Give users some breathing room. Users learn quickly and gain a fast sense of mastery
when they are placed "in charge." Paradoxically, however, people do not feel free in the
absence of all boundaries (Yallum, 1980). A little child will cry equally when held too
tight or left to wander in a large and empty warehouse. Adults, too, feel most comfortable
in an environment that is neither confining nor infinite, an environment explorable, but
Use status mechanisms to keep users aware and informed.
No autonomy can exist in the absence of control, and control cannot be exerted in the
absence of sufficient information. Status mechanisms are vital to supplying the
information necessary for workers to respond appropriately to changing conditions. As a
simple example, workers, failing status information, will tend to maintain heightened
pressure on themselves during slow periods, until the moment the work actually runs out.
This will stress and fatigue them unnecessarily, so that when the next rush occurs, they
may be lacking the physical and mental reserves to handle it.
Keep status information up to date and within easy view