advancement of traditional LED displays (it adds "quantum dots" to the pixels). But it's complete marketing designed to confuse with OLED. It's working - most people think they are the same thing.

OLED is a completely different technology where each pixel is it's own emissive dot, which makes really good color, contrast, and black levels possible, not to mention an incredibly thin display (because it doesn't need a back light).

Only LG and Sony make OLED displays (for TV's at least - Samsung uses OLED for their Galaxy phone displays). Samsung is trying to get other manufacturers to pick up the QLED brand, but so far it's just a Samsung thing.