User Experience ( UI , UX ) notes:

UX is an acronym for "user experience"


DEFINITION:
Best definition can be found here: http://www.helloerik.com/ux-is-not-ui


USEFUL ARTICLES:

• About Hamburger Menu
• http://lmjabreu.com/post/why-and-how-to-avoid-hamburger-menus/
• About Golden Ratio
•  http://en.wikipedia.org/wiki/Golden_ratio
•  Introduction to Usability by Jakob Nielsen
• http://www.nngroup.com/articles/usability-101-introduction-to-usability/
•  User Interface (UX) Techniques by Janne Jul Jensen
• http://lnkd.in/YxRKQm 
• UX Design: An Introduction by Scout Stevenson
• http://lnkd.in/987zK8
• Dropdown
• www.lukew.com/ff/entry.asp?1950
• About 10 Usability Heuristics by 
• http://www.slideshare.net/crafted/10-usability-heuristics-explained

All useful material that I found can are here:
http://dominiksymonowicz.blogspot.co.uk/search/label/ux