Check this wiki article. Everything is an LCD... well if not crt or plasma.http://en.wikipedia.org/wiki/TFT_LCD
IPS was a huge step forward when they went from TN. Its simply the way they switch "the crystal molecules move parallel to the panel plane instead of perpendicular to it" However TN panels are cheaper to produce. Now Samsung has come out with PLS which is similar to ips? but cheaper to produce. I just ordered an s24a850 and will give PLS a shot.