The rapid growth of RIA technology into the lives of every day people just a few years ago has carried both the usability and user experience industries to a new high in popularity. The success of software (particularly on the web) has driven both of these terms into our vernacular, and yet they are still often confused or thought to be synonymous. This post is meant to help those new to the field or unfamiliar with the intricacies of design to understand the differences between the terms.
Usability refers to the ease with which a user can accomplish his or her goals using any tool. Coming from the field of human factors engineer, usability has been applied to software in the fields of human computer interaction and includes many important ideas from psychology and statistics. Usability is fundamentally qualitative but involves the heavy application of quantitative data to identify areas of weakness and suggest improvements. The study of usability often focuses on performing extensive tests with large groups of individuals, sometimes involving in depth techniques like eye tracking to determine how users interact with interfaces and any areas in which they get lost. Highly usable interfaces are often lauded for being intuitive, simple or extremely learnable.
Somewhat in contrast, user experience refers to the way a user perceives his or her interaction with a system. User experience design encompasses both interaction design and visual design and seeks to promote an interface that is pleasing to the user. The study of user experience often focuses more on the psychological impact of interacting with the system than pure usability does, and user experience experts will spend their time performing both ethnographic and psycho-graphic research to construct their interfaces. User experience design is more qualitative than usability, though the two are not necessarily exclusive. For instance, often times user experience experts turn their designs over to usability experts to test and validate them in the field.
Usable for certain.
By far the easiest (and probably most over-cited, please forgive me) to distinguish these two comes on lauded usability expert Jakob Nielsen's homepage, useit.com. Jakob has dedicated a lifetime to the study of usability, and his website represents a page that is extremely easy to interact with. Everything is front and center, easily searchable, with important ideas stressed through bold text. Yet despite its high level of usability, the lack of interesting layout, design, or even typography makes the site rather boring and feel uninspired. I can accomplish my goals here easily, but I probably won't have much fun in the process.
