User experience (UX)
User experience (UX) defines how a visitor perceives your website or app, and how he or she feels like after interacting with the system, service or product you offer. In simpler terms, this concept defines how a user feels about every interaction with your website or app.
Although UX is sometimes used interchangeably with usability, it is not the same thing. Usability is just one of the elements that influence the user experience, and it refers mainly to the user interface (UI), while UX takes into consideration all the elements that can make the system, product or service more effective and enjoyable to use.