Luke Wroblewski has documented some of the questions and his answers (Part 1 Part 2) on usability to them during the Usability 2.0 event. It is a good collection of the basics, fundamentals and thoughts on recent developments in simple and clear language.
Take time to read through, I have found some things which can help me understand usability and incorporating usability in the design. Here are some of the good ones:
As outlined by Terry Winograd, humans have three predominant ways of interacting with the world: locomotion (moving from place to place); conversation (communication with others); and manipulation (using/editing/creating).
For any type of usability testing, Iâ€™d say a crucial best practice is objectivity. Being able to observe what you are seeing people do without a subjective viewpoint is one of the traits Iâ€™ve come to admire most in usability professionals. Part of that is being open to new insights. If you have a predetermined point of view, youâ€™re likely to mostly see what you assume you will beforehand.
There are some good lessons in there. Unlike other disciplines, usability is personal. Instead of the user groups, there is need to think about the individual user. Discoverability is one of the difficult things to incorporate. There has to be some relation between the content priority and the discoverability to be able to achieve consistently.