This LCD has space for display with 2 lines of 16 characters. The display has white text on a blue background and uses the HD44780 'parallel interface' chipset and works on 5V.
When you connect this module directly to the arduino, connect a resistor of 2K ohm to the contrast pin and 100 ohm to the backlight pin. Instead of the 2K contrast resistor, you can of course also connect a potentiometer to adjust the contrast.
With the LCD interface module the module can easily be controlled via the I2C protocol:
[product display] 10118 [/ product display]