Abstract: A digital data display system in which the display device includes a plurality of random access stores into which character cell definitions are loaded from a remote central processing unit. A character cell may be a 9.times.16 picture element matrix and each is defined in the CPU according to the requirements of a display request received from a users application program. The system control services include a graphics manager and graphics routines which construct a character buffer and character cell definition table according to the picture to be displayed. A character cell definition that is required more than once in a picture is only included once in the definition table, the character buffer having the required number of pointers to the one definition. When the character buffer and character definition table have been constructed, they are transmitted to the display device using a data communication system. The system can be used for color or monochrome displays.