Plasma technology is not outdated, but some of the companies have stopped produce it. Plasma was the first flat screen technology that was sold. And still are what is counted as best for showing film. Led TV is as told here an Lcd with led backlight. The thinnest screens of today is what we call edge-led type lcd screen.But the best quality picture TV is still back led type. In the future there will be better technologies coming. One is OLED (organic light emitting diode) and one is QLED (Quantum Dot Light Emitting Diode) OLED is today allready in use in mobil phone displays.AMOLED is a type OLED screen. OLED and QLED do not need backlight and will give a better picture in all angles from the screen. As you know the cheapest TVs change colours very soon side from head on position. But as of today there is just a few companies that produse the flat screen panels which is in the tv today. Samsung is the world biggest produser.