What is UCD?
"An approach to designing ease of use into the total user experience with products and systems. It involves two fundamental elements - multidisciplinary teamwork and a set of specialized methods of acquiring user input and converting it into design."
Vredenburg, K., Isensee, S., and Righi, C. (2001). User-Centered Design: An Integrated Approach (Software quality institute series). Prentice Hall