User experience web design focuses on a website visitor’s interaction with the site. In reality, it is a subset of a company’s (or organization’s) approach to its customers.
User experience (UX) design is not the same as user interface (UI) design, although the UI affects the UX. Usability is yet another important concept, but it is usually consider a characteristics of a user interface: is it easy to learn, efficient, aesthetically pleasing and so forth.
Each of these concepts is related to user-centered design.
UX design is a term coined by Don Norman in his book The Design of Everyday Things. At the time, he was Vice President of the Advanced Technology Group at Apple and he “thought Human Interface and usability were too narrow: I wanted to cover all aspects of the person’s experience with a system.”