A Text User Interface (TUI) is a type of user interface that allows users to interact with a computer program through text-based commands and visual elements displayed in a console or terminal window. Unlike graphical user interfaces (GUIs), which use images and icons, TUIs rely on characters and symbols to represent options and information. This makes them lightweight and efficient, often used in environments where resources are limited. TUIs are commonly found in applications like text editors, file managers, and system administration tools. They can be navigated using keyboard shortcuts, making them fast for experienced users. While they may seem outdated compared to modern GUIs, TUIs remain popular for their speed and simplicity, especially among developers and system administrators.