The notions of UX (User eXperience) and UI (User Interface) are now essential in the field of web design. However, they should not be confused. The UX is not the UI, however, the UI is part of the UX.
UX is a complete process that includes content optimization, user testing, navigation data analysis, feature optimization, site architecture design, customer satisfaction, Ergonomic design through prototyping, reflection on human / machine interactions. Finally, the UX also includes the UI which focuses on visual identity, graphic design and editorial charter.