What is a TUI?
A text-user interface is a method for communicating with computers through text. Instead of clicking buttons with a mouse, users type commands on a keyboard. The computer responds by displaying text-based information on the screen. TUIs were common before graphical user interfaces (GUIs) became popular in the 1980s and 1990s.
How TUIs Work
In a TUI, users enter commands by typing them into a prompt, which is usually a blinking cursor on a dark screen. The computer reads the command and executes it, then displays the results as text. The interface uses only characters, letters, and numbers to show menus, options, and information. Some modern TUIs use colored text and simple graphics made from text characters to make them easier to use.
Examples of TUIs
Common examples of TUIs include the Windows Command Prompt, macOS Terminal, and Linux shell. Many system administration tools, programming environments, and database systems use TUI or text-based commands. File managers and text editors can also operate as TUIs. Modern TUIs sometimes use formatted menus and boxes created from text characters to improve usability.
Advantages of TUIs
TUIs are very efficient for experienced users because typing commands is often faster than clicking through menus. They use very little computer memory and processing power, making them ideal for older computers or remote systems. TUIs are also useful when a graphical display is not available or when managing servers over a network connection. They provide direct control and can perform complex tasks with single commands.
TUI vs GUI
Graphical user interfaces (GUIs) use windows, icons, and mouse clicks, making them easier for beginners to learn. TUIs require memorizing commands but offer more speed and power for advanced users. Most modern computers use GUIs, but TUIs remain essential for technical work, system administration, and programming. Many professionals use both TUIs and GUIs depending on the task. 
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