Questions about SD card boot and eMMC image flashing

Hello all,

I have a few questions and I found different answers no solid reference one:

  1. What is the difference between flasher and pre-built image?
  2. What is the correct way to boot an image from SD card?
  3. How to flash the on-board eMMC with a pre-built image? a flasher image?
    Thanks in advance!

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