CUI and GUI
Most computer users are familiar with GUIs (Graphic User Interfaces) provided by the Windows or Mac computer but may not be familiar with CUIs (Character User Interfaces).
In the GUI, users mostly use a mouse to select files, directories, or tasks to control the operating system supported by the keyboard to make character inputs into the OS.
In the CUI, the mouse doesn't play a role. All actions by users should be done through the keyboard including the selection of files and directories. The terminal or command line in Linux OS and Mac OS or the command prompt in Windows OS are CUI-based.
On personal computers, CUI-based systems run on GUI-based systems. For example, when you use Terminal in Mac OS or connect to a Linux OS remote server through your laptop, you are using a CUI application on your GUI-based system. Thus, you can still get some assistance with your mouse from the GUI, but the mouse assistance is not supported by the CUI itself.
Because of its nature, the GUI-based system is more intuitive; however, it consumes more computer resources and is slower than the CUI-based system. On the other hand, the CUI-based system uses limited computer resources, which means it's faster.
It may take time to get used to handling a computer on CUI but your work can be faster once you master it.
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