A Graphical User Interface (GUI) is a type of user interface that allows users to interact with electronic devices using visual elements such as icons, buttons, and windows, rather than text-based commands. GUIs are designed to be intuitive and user-friendly, making it easier for non-technical users to operate computers, smartphones, and other devices. The advent of GUIs revolutionized computing by providing a more accessible way for people to interact with technology, moving away from the command-line interfaces that required knowledge of specific syntax and commands.

GUIs are built using a combination of graphics, text, and input devices like a mouse, keyboard, or touchscreen, allowing users to navigate and control the device through direct manipulation of visual elements. The design of a GUI plays a crucial role in the overall user experience (UX), influencing how easily and efficiently users can accomplish tasks. Modern GUIs are found in operating systems like Windows, macOS, and Linux, as well as in mobile platforms like iOS and Android. The principles of GUI design are also applied to software applications, websites, and embedded systems, making GUIs a fundamental aspect of human-computer interaction.