20 Simple, but important ‘internet’ things!
Knowing how things work is the most important aspect of using them effectively. For many non-technical users which is the large population of internet user community, knowing about some key elements of internet is really useful.
The best & simple resource for that experience comes via 20 Things I Learned About Browsers and The Web by Google Team: 
It is very refreshing for technical people too HTML 5 ready online book!
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