I was interrupted before I submitted this comment, and I see you’ve gotten some replies since I wrote the draft, but my comment goes a little deeper, so I figured I’d still add on.

FALD and mini LED are similar in function, but mini LED has a couple advantages. Since the actual LEDs are smaller, you can place a larger quantity of them behind the LCD panel than traditional LEDs. This allows for more dimming zones to reduce the halo effect, and also enables higher peak brightness which means better contrast.

IPS and VA refer not to the backlight system, but to the actual liquid crystal display panel that sits in front of the backlight. The LCD itself is like an array of microscopic window shutters that can turn clear or black. By placing this LCD behind a color filter layer, the LCD can control light passing through each subpixel (red, green, blue) of the filter layer to produce the appropriate color for each pixel. Each panel type (IPS, VA, TN, etc ) has its own set of advantages and disadvantages when it comes to cost, response time, image ghosting, viewing angle, color accuracy, contrast, etc. Each of those panel types could be paired with an edge-lit backlight, FALD backlight, or mini LED backlight.

OLED is a completely separate technology altogether. Instead of putting an LCD filter layer in front of a backlight, OLED puts individual white LEDs behind each red, green, and blue subpixel of the color filter layer. That means instead of a liquid crystal layer blocking out backlight (which is imperfect and still bleeds light, hence the FALD halo effect), an OLED simply does not emit light for that pixel/subpixel, allowing perfect blacks and better color accuracy.

QLED and QD-OLED trade the white LED backlights and white OLED panels for blue light and discard the traditional color filter layer, replacing it with a sheet of quantum dots that use some kind of black magic optical fuckery to change blue light into red and green as well.