User experience (UX) designers are responsible for creating an optimal experience for the user when they interact with a digital product (such as an app or a website). UX design involves the design of the entire process of acquiring and integrating the product, including aspects of branding, design, usability and function.
User interaction (UI) designers are primarily concerned with how a user navigates through a digital product. UI is an integral aspect of user experience (UX) that consists of two major parts: visual design, which conveys the look and feel of a product; and interaction design, which is the functional and logical organization of elements.
UI/UX + Product Design. UI design is considered a UX function, so you will often see UI/UX used interchangeably in job titles and job descriptions, or it may fall under the responsibility of a product designer.