2x16 Character LCD is most popular display component for small controller like Arduino, but most of these LCD uses parallel interface. In most of the case, you will need 10 pins to control it or to display message on it. 8-pin are for the data, Enable and Latch pin for signal control. Minimum, you will need 6-pin for 4-bit mode interface. Still a lot of pins being used up :(
This I2C module for LCD will help you save all those precious pins. This module will only need 2 GPIO pins (specifically I2C pins) to send message to Character LCD.
It comes with potentiometer for LCD contrast adjustment, and configurable I2C Address through A0, A1 and A2 pads. Anyway, the default address is 0x3F or 0x27. There is also a mini jumper to activate or deactivate the backlight.