i use 16X2 LCD compatible with Hitachi's 44780 driver, you can easily recognize these with the 16-pin interface
Not exactly. The LCD interface uses 14-pins and that is what is shown on the Hitachi datasheets and those derived from that datasheet.
Most of the original LCD modules did not have a backlight and many of those that did required a special power supply that connected to two pads on the pc board near the end of the display.
Many, if not most, of the current LCD modules have an LED backlight that is powered via two pins lined up with the original 14. Usually they are next to pin 14, but sometimes they are at the other end next to pin 1. This is a convenient location but it does not change the LCD interface from 14 pins to 16 pins.
The LCD information provided in the original Hitachi datasheet is entirely appropriate for these '16-pin' devices but someone who is not familiar with the function of the extra two pins might not realize this since the Hitachi datasheet makes no mention of these extra pins.
I know that the tutorial in the playground calls this a 16-pin interface but that does not make it right. About a year ago it took me several months to get the program example on that page corrected and the information about dealing with pin 5 emphasized and I didn't want to push my luck in trying to correct this part of the page.