Welcome to the New LiquidCrystal library for Arduino. This library is a derivate of the original LiquidCrystal Library as sourced in the Arduino SDK. The library supports most Hitachi HD44780 based LCDs or compatible and they can be now connected to any project using (4, 8 wire parallel interface and an I2C IO port expander).
The main changes to the LiquidCrystal Library is that it has been changed to be a pure abstract class from which particular implementations derive from. Therefore, it is possible to create new drivers to the library by simply inhering from the base class and develop the functions that are specific to accessing the LCD.