Introduction - If you have any usage issues, please Google them yourself
Character display has an character buffer to which you can write ASCII codes which it will represent as letters and nubers on the display.
On a graphical LCD, you program each pixel indipendantlu (actualy in blocks of eight,as you write byte per byte). To write text on graphical LCD you must have a table with graphical representation of ech character (which is internaly handled by the character LCD).