I am working on improving skills of building web and mobile app prototype , but sometimes these terms confuse me a bit ,should we say that UI is the front page while UX is the principle behind building the interface? and how can we tell the difference between UX and Interaction design? is the relationship between them similar to the relation between sub-category and main category?
UI is literally the interface – the screen/s that you use to interact with a product. UX encompasses the entire experience (that UI + the rest of the journey). So essentially exactly what you’ve said, but UI isn’t always the ‘front’ page.
Interaction design refers specifically to the design of digital products, whereas UX can mean any experience.
Does that help?