User interface, commonly abbreviated as UI, describes the way a user accesses and interacts with a system. It’s the physical characteristics of the application, whether digital or tangible; it’s literally the part that you interact with, the face of the system to the user, and how they think of it. A UI should meet the needs of the user with simplicity and elegance.
Flat UIs have become fundamental in creating successful user experiences because they offer a straightforward, minimalistic approach to design. Utilizing two-dimensional illustrations and lessening the use of shadows, gradient textures, and three-dimensional treatments is aesthetically pleasing and helps users to process the content quickly without distraction.
Along with the user experience, UI is important for driving broad user adoption. For example, not all users are “pivot-table” compliant. Focus in on the target user and their needs and capabilities, and deliver analytics in a UI that is engaging and fits that end-user.