The iPhone X is rumored to have an OLED screen — here's what OLED is and how it's different from past iPhones (AAPL)

Apple is set to announce a slew of new products on Tuesday, including three new iPhones: the iPhone 8, iPhone 8 Plus, and iPhone X.
There are said to be several major differences among the three phones, but one of the biggest changes is the screen — the iPhone X will have a new OLED screen, while the iPhone 8 and 8 Plus will have an LCD screen like Apple's previous phones.
The OLED technology is new for Apple, but anyone who uses Samsung phones (or the Google Pixel, or the new Essential Ph