hose who work on UX (called UX designers) study and evaluate how users feel about a system, looking at such things as ease of use, perception of the value of the system, utility, efficiency in performing tasks and so forth.
UX designers also look at sub-systems and processes within a system. For example, they might study the checkout process of an e-commerce website to see whether users find the process of buying products from the website easy and pleasant. They could delve deeper by studying components of the sub-system, such as seeing how efficient and pleasant is the experience of users filling out input fields in a Web form.
Compared to many other disciplines, particularly Web-based systems, UX is relatively new. The term “user experience” was coined by Dr. Donald Norman, a cognitive science researcher who was also the first to describe the importance of user-centered design (the notion that design decisions should be based on the needs and wants of users).