it is the design of any user interface in which usability is as important as appearance.
UX stands for User Experience (literally: “user experience”). That is, this is what experience / impression the user receives from working with your interface. Does he succeed in achieving the goal and how easy or difficult is it to do.
And UI is User Interface (literally “user interface”) – how the interface looks and what physical characteristics it acquires. It determines what color your “product” will be, whether it will be convenient for a person to hit the buttons with his finger, whether the text will be readable, and the like ...
it is the design of any user interface in which usability is as important as appearance.