system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What's an OLED display and how is it different than a regular LED one?
gpt
A real LED display is like what you see on billboards, where the display is made up of thousands of individual LED lights. An OLED display is sorta similar, only on a much smaller scale. Each pixel is an individual LED that gives off light, but they're "grown" in that a chemical reaction deposits a matrix of tiny LED pixels.

Any laptop or TV marketed as having a "LED display" though, is really just a marketing term used for LCD displays that are backlit with LEDs. The way LCD displays work is they're a sheet of glass that can be made opaque when voltage is applied to it. So, you have a bunch of lights behind it, and the color and brightness of the pixels is determined by how you block out that light. Back in the day, they used fluorescent bulbs for this, but they had issues like flickering, dimming, and outright dying. They weren't replaceable, so when they died so did your screen. That's why LEDs are better for backlights.

Since LCDs are blocking out light you can't get really dark blacks. Since OLEDs are actual bulbs that turn on, when they're off they're 100% pure black. LCDs are far cheaper to manufacture, especially for large panels, which is why you mostly only see OLED used on phones not TVs.