Graphical user interface simply means that the interface in which there is a representation of the graph I would like to say you one thing that when you use your laptop then your laptop is meaningless till now there is some image on your laptop yes you imagine when your laptop is not working properly are you also imagine when the screen of your laptop is not working properly but your CPU of your laptop is working properly then you like your laptop or not definitely you will not like your laptop why you will not like your laptop the main reason behind this is there is no graphical representation of your laptop.
so I am going to see you the concept of graphical user interface this will help you to understand the concept of graphical user interface very clearly.
I try to remember one thing that when there was no any graphical interface then How the people interact with each other and what was the condition of that time when there was no any graphical interface available or there was no any technology of graphical interface then I find one thing that at that time people tried to make a painting and in painting the painter try to give some feeling or you must give some types of a situational conditions which attracts the people and when the people view the image that feel something but the time change and know the time of graphical interface that changed all the painting style know the painting is done with the laptop on your computer no there is no any need of pen or pencil for doing painting this is how the graphical interface the really changed the world.
I also find some interesting things like if you want to explain the earth and virtual way to the children then definitely children will not able to understand how was the earth and how Earth is revolving then you feel one thing that is really graphical user interface will help to clear the doubt of the children that the Earth is round and Earth is revolving so I find one thing that they were the need of graphical user interface.
It is really very important that you try to make your graphics very clear because if the feeling of your graphics will become more powerful than more and people will like your graphics and ultimately the seat of your graphical interface is like the more and more people and if you say in indirect way your graphics sheets or your graphics will go to number of peoples and ultimately this is a success of your graphical interface in gaming it plays a crucial role and any grammar should have one thing in common that the graphics should be very attractive.