User interfaces are composed of one or more layers, including a human–machine interface (HMI) that typically interfaces machines with physical input hardware (such as keyboards, mice, or game pads) and output hardware (such as computer monitors, speakers, and printers).

User interface (UI) design or user interface engineering is the design of user interfaces for machines and software, such as computers, home appliances, mobile devices, and other electronic devices, with the focus on maximizing usability and the user experience.

A graphical user interface, or GUI [a], is a form of user interface that allows users to interact with electronic devices through graphical icons and visual indicators such as secondary notation. In many applications, GUIs are used instead of text-based UIs , which are based on typed command labels or text navigation.

A User interface allows a user to interact with a machine. User interfaces mainly provide two things: input The user can change things; he or she can change how the machine works, or give more information to the machine. Many machines can be very dangerous.

The user interface (UI) is the point of human-computer interaction and communication in a device. This can include display screens, keyboards, a mouse and the appearance of a desktop. It is also how a user interacts with an application or a website, using visual and audio elements, such as type fonts, icons, buttons, animations and sounds.

User interface design (UI) or user interface engineering is the design of our machines and software interface such as the interface of your computer, printer, phones, etc. It helps the user interact with the system in order to increase the user experience and enhance efficiency.

Computers can display information and let the user give commands to it using two methods: a command line interface (CLI) or a graphical user interface (GUI). In a command line interface, the user types commands using the keyboard to tell the computer to take an action.

With the introduction of the Xerox Star in June 1981, the graphical user interface, as it is known today, arrived on the market.

User interface (UI) design is the process designers use to build interfaces in software or computerized devices, focusing on looks or style. Designers aim to create interfaces which users find easy to use and pleasurable. UI design refers to graphical user interfaces and other forms—e.g., voice-controlled interfaces.

The history of the graphical user interface, understood as the use of graphic icons and a pointing device to control a computer, covers a five-decade span of incremental refinements, built on some constant core principles.