https://www.techradar.com/news/television/oled-tv-what-you-need-to-know-1056228

We're not exaggerating when we say that OLED is most likely the future of television displays. The premium screen technology is still expensive, but is seeing wider implementation and improvement all the time, even becoming the new display of choice for the iPhone X and its newly announced successors: the Phone XS and iPhone XS Max. 

But what is OLED? Standing for 'Organic Light Emitting Diode', the acronym describes a type of panel that TVs use – like LED-LCD, plasma or CRT. It's different from the other types of panels that have come before it, but the overarching idea is exactly the same: OLED panels help bring images and video to life in front of your eyes.