UX is short for "user experience," but that can mean different things to different people.
In a general sense, user experience can refer to the experience any user has with anything, whether it's a physical or digital interface, whether it's a product or service, etc. Under this broad definition, the act of using a can opener to open a can of beans could be considered a "user experience." The term was originally coined within the context of software, but was intended to encompass the entire experience of being a software user, which could include printed documentation, customer support calls, etc., so this is probably best described as the original meaning of the phrase. In most cases, however, those kinds of interactions would now fall under the category of "customer experience" (or CX) rather than user experience specifically.
In common contemporary usage, the phrase "UX" or "user experience" typically refers specifically to digital experiences: computers, mobile devices, tablets, kiosks, web-enabled refrigerators, etc. This is how most people use the term, and it's how I'll be using it throughout these pages.
There are also some people who specifically use the term "UX" to refer to the architectural side of digital interface design (site maps, wireframe diagrams, process flows, etc.), in contrast with "UI" (user interface) which refers more to the visual or aesthetic side of the process. This usage used to be called "information architecture" but use of that phrasae has been in decline, so people often substitute "UX" for the things they used to call information architecture. This is an unfortunate and misguided usage of the phrase, and is generally discouraged within the industry. Technically, UI is an aspect of UX, rather than UX and UI being separate stages of a design process.
By now you're probably feeling like the language for all these concepts can be frustratingly ambiguous, and you wouldn't be wrong. The industry tries to adopt somewhat accepted terms where it can, but the truth is that people are just making this crap up as they go, and terminology is constantly rising and falling in popularity, and being used and misused by a diverse and every-changing group of people. While the principles and concepts have remained almost the same since the early days, the vocabulary to describe them is constantly in flux.
At a very high level, the following elements should certainly be considered when thinking about what UX is:
- User research and user testing
- User psychology
- Prototyping and architecture
- Usability / accessibility / universal design
- User interface design
UX is typically closely associated with design, such that "UX" and "UX design" are almost synonymous in current usage.