UI (User Interface)
UI stands for “User Interface”. User interface is the space where interactions between humans and machines occur, for example with an app or with a computer. Generally, the goal of user interface design is to produce a user interface that makes it easy, efficient, and enjoyable to operate a machine in the way which produces the desired result. This generally means that the operator needs to provide minimal input to achieve the desired output, and also that the machine minimizes undesired outputs to the user.
A mobile user interface is the graphical and usually touch-sensitive display on a mobile device, such as a smartphone or tablet, that allows the user to interact with the device’s apps, features, content and functions.
User interface design in games differs from other UI design because it involves an additional element – fiction.
Read more about the importance of UI here.