Difference Between CUI And GUI Operating System?

CUI stands for Character User Interface

GUI stands for Graphical User Interface

the GUI is the user interface in which user interact
through the application by making uses of graphics, whereas
in CUI the user has to interact with the application by
making use of the codes

CUI stands for Character User Interface,it means that you have to type commands to interact with your computer. E.g. - In DOS for every thing we type the commands.
GUI stands for Graphical User Interface,it means that you no need to type commands to interact with your computer instead you have to click with the help of mouse on the icons of readymade commands.

CUI = Character User Interface = like a DOS prompt, you just type in commands and results are displayed in text  GUI = Graphical User Interface = like Windows, you have lots of pretty things to look at, more colours, and probably a mouse to control the cursor....it's supposed to be more user-friendly because it is more intuitive, i.e. People will find it easier to figure out how to click on something than trying to remember lots of commands and parameters and stuff