UX is an abbreviation for User Experience. It describes the ease of use that visitors in a website are presented with. It is often used in relationship to UI, which stands for User Interface. The User Interface is a term used to describe the presentation of the website or app. So, in practice, you have to improve the UI, so that visitors will have a better UX. The UI is the code and business side of the equation, and the UX is how it impacts visitors.