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Authoring and Design for the WWW

DESIGN INTO PRODUCTION

User-centred design

Some rules

The following are example rules from a standard text on interface design (Brown 1988), showing how they can be applied to the Web.

Display design

Use invariant fields on each screen
If similar items of information are to be shown to the user or the user is expected to enter such information then similar locations on screen should be used throughout. For example, a Help button should not appear in different locations on various pages. Type size, style and colour should be similarly consistent: this is a case where the Web used to impose its own rules, but now using the COLOR and SIZE attributes we have the freedom to make mistakes.
Define and use terms consistently
One word such as Home Page must not be used to mean different things. In fact the whole idea of Home in Web pages is best avoided in a user-centred design a page may be home to the publisher, but not to the user.
Present lists in useful orders
Lists, for example of linked pages, should be arranged in a way suited to the use and user, not the publisher. Depending on the purpose, this may be alphabetical, classified, logically grouped, hierarchical and so forth.
Present similar information in similar formats
Variety which has no meaning is counter-productive. Differentiation should only be used where it signals an important difference to the user.
Make instructions distinct from data
Items which are part of the furniture of the system, or which are rubric telling the user what to do, should not look like content material, nor vice versa.
Present information in the form it is used
This is the essence of successful design for users. Designers must put themselves in the user's shoes when deciding how to give or request information. For example, the questions posed in a Web-based form should be posed in terms which make sense to the intended user, avoiding Web jargon and omitting anything which would only be comprehensible to the publisher.
Minimise cursor/pointer movement
If there are two hypertext or other controls which are frequently needed one after the other, they should be placed together on the screen (as are the go-forward and go-back buttons in the Netscape interface).
Use of icons
Icons can be used for compactness and memorableness. However they are frequently no improvement on text, sometimes worse.

Dialogue Design

Provide input acknowledge and progress indicators
See Feedback above for an example.
Indicate modes
A mode' is a state of the system. For example, in computer menus, an item will be disabled (grey) if it cannot meaningfully or legally be selected in the current circumstances. If there is something users must not do at a certain juncture, this should be clear to users before they attempt to do it. It is important to avoid unnecessary modality: designers must not prevent users doing things they have a perfect right to do!
Give access to settings
The user can be helped and reassured by having permanent access to status information, for example by indicating to users where they are on a graphical map of the site. In addition, anything which could reasonably be interacted with, should indeed be interactive. So a map of the site should not only provide feedback as to the user's current location, but also be a control panel which the user can click on to change that location.
The frame facility of some browsers is helpful in allowing controls to be constantly present even when other information is changing.

Users' errors

Users will make errors, especially as systems become more complex. User-centred designers work with error in mind, trying to prevent misunderstandings and slips by the user, but not supposing that such errors will never occur.

When finally users do make mistakes, error messages should be instructive, polite, brief, appropriate to users, consistent, specific and directive.

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