The visibility principle of under interface design

Write out around 7 minute ( around 4 pages) on The visibility principle of user interface design based off of ‘Software for Use: A Practical Guide to the Models and Methods and Usage-Centered Design’ written by Larry L. Constantine and Lucy A.D. Lockwood. Firstly explain the visibility principle ( do not touch on any other principle) and the expand on it. Use at least 2 examples of real world application (important websites).

Seperate each point in bullet point form. This is a presentation, not a paper. Start with a quick summary of what this principle is and then get into the main points and why it is so important.

These are the main points needed to be covered.

All points need to be sourced. Mainly use the book, but if you use some information from outside the book then cite everything.

The visibility principle. Your design should keep all needed options and materials for a given task visible without distracting the user with extraneous or redundant information. Good designs don’t overwhelm users with too many alternatives or confuse them with unneeded information.

https://en.wikipedia.org/wiki/Principles_of_user_interface_design

http://www.amazon.com/exec/obidos/ASIN/0201924781/ambysoftinc/104-5066916-9969502