Don't Make Me Think is a useful book about human computer interaction and web usability. A quick look at key lessons from the book:

[From the Great Books Series. Also see The Success Manual  - Encyclopedia of Advice, which contains summaries of 100+ Most useful books.]

1. Rule # 1 Don’t make me think! Get Rid of questions marks in thought balloons
2. How we really use the web: Scanning, Satisficing and Muddling Through
3. Billboard design 101: Design for scanning, not reading.
4. Billboard design 101: Design for scanning, not reading. – Create a clear visual hierarchy – Conventions are your friends – Break pages into clearly defined areas – Make obvious what is clickable – Keep the noise down to a dull roar
4. Why users like mindless choices Law # 2: It doesn’t matter how many times I click, as long as each click is a mindless, unambiguous choice.
5. Omit needless words : Happy talk must die!; Instructions must die!

Law # 3: Get rid of half the words on each page, then get rid of half of what is left.
6. Street signs and Breadcrumbs The Trunk Test - What site is this?  What page am I on?  What are the major sections of this site? What are my options at this level? Where am I in the scheme of things? How can I search? People won’t use your website if they can’t find their way around it.
7. The Home Page is beyond your control 5 Questions a Home Page should answer -  1. What is this? 2. What do they have here? 3. What can I do here? 4. Why should I be here and not somewhere else? 5. Where do I start?
8. Arguments about usability are a waste of time:  “Everybody likes ______”  The myth of the Average User The antidote to religious debates: usability testing.
9. Usability testing on 10 cents a day : It is never too early to test -  Test 3 to 4 users; It doesn’t matter who you test; Choose someone who is patient, calm, empathetic, good listener to conduct tests;  Encourage all stakeholders to attend; Types –  “Get it” testing; Key task testing ; Review results right away The antidote to religious debates: usability testing.
10. Usability as common courtesy: Goodwill is diminished by: Hiding information I want, Punishing me for not doing and easy things your way, Asking excessive, Faux sincerity, Putting sizzle in my way errors, Site looks amateurish
Goodwill increased by: Make 3 main things obvious, Tell me what I want to know, Save me steps where you can information, Real FAQs, not marketing pitches, Make it easy to recover from, When in doubt, apologize.

11. Accessibility, CSS and You: Fix usability problems that confuse everyone - Read an article, Read a book, Start using CSS, Go for the low hanging fruit