WYSIWYG (What You See Is What You Get) (HI Guide)

Inside Macintosh: Macintosh Human Interface Guidelines / Part 1 - Fundamentals: Chapter 1 - Human Interface Principles / The Human Interface Design Principles

WYSIWYG (What You See Is What You Get)

Don't hide features in your application by using abstract commands. People should be able to see what they need when they need it. For example, menus present lists of commands so that people can see their choices instead of having to remember and type command names.

People should be able to find all the available features in your application.
If you find a need to initially "hide" features, do it in a way that gives people information about where they can find more choices. A stepped interface,
by revealing relevant information to users in steps, shows the choice most users want most of the time while providing a way for the user to get more choices. For information on stepped interfaces, see the guidelines in the section "Using Progressive Disclosure" on page 35 in Chapter 3, "Human Interface Design and the Development Process."

Make sure that there is no significant difference between what the user sees on the screen and what the user receives after printing. Let the user be in charge of both the content and the format (spatial layout as well as font choices) of the document. When the user makes changes to the document, quickly and directly display the results; the user shouldn't have to wait for a printout or make mental calculations of how the document shown on the screen will look when it appears on the printed page.