In embedded systems and hardware programming, "565" refers to a 16-bit color format (5 bits for Red, 6 for Green, 5 for Blue) used to save memory on small displays like those on Arduinos or ESP32s.

The label "565" appears in several specific educational contexts where video production (MP4) is a core component:

Developers often need to convert standard MP4 files into a raw RGB565 format to play them on microcontrollers from an SD card.