? Alben (1997)
: All the aspects of how people use an interactive product: the way it feels in their hands, how well they understand how it works, how they feel about it while they’re using it, how well it serves their purposes, and how well it fits into the entire context in which they are using it.
? [[http://www.nngroup.com/articles/definition-user-experience/ | Nielsen Norman Group]]
: "User experience" encompasses all aspects of the end-user's interaction with the company, its services, and its products.

? UX 
: User Experience Design - Umbrella term for all of user research, interaction design, information architecture, graphic design, user testing, etc. See http://www.jjg.net/elements/pdf/elements.pdf for one possible overview.

? User Interface Design
: Sometimes used as an umbrella term like UX. Sometimes used to talk specifically to talk about a visual designer who specialises in user interfaces. Sometimes used to talk about somebody who specialises in designing how users interact with a whole product (the latter is often called Interaction Design these days).