The Nokia 5110 is a basic graphic LCD screen for lots of applications. A much richer information set can be displayed on this screen.
It uses the PCD8544 controller, same used in the Nokia 3310 LCD. The PCD8544 is a low power CMOS LCD controller/driver, designed to drive a graphic display of 48 rows and 84 columns. All necessary functions for the display are provided in a single chip, including on-chip generation of LCD supply and bias voltages, resulting in a minimum of external components and low power consumption. The PCD8544 interfaces to microcontrollers through a serial bus interface.
There is an Arduino library and MikroC library