How does the FT8XX touch screen work?

Please refer to this link for detailed description on how a 4 wire resistive touch screen works. http://www.sparkfun.com/datasheets/LCD/HOW%20DOES%20IT%20WORK.pdf

Please refer to this link for detailed description on how a capacitive touch screen works.
https://www.youtube.com/watch?v=BR4wNq6WGkg