Difference between App and Boot bin

What is the difference between App and boot bins.
How to flash both boot and app bin files

The ‘Boot’ (AppBoot) area is located at 0x00000000 in the flash memory and performs firmware update and recovery. ‘App’ area is located at address 0x00007000 and performs ‘Serial to Ethernet’ function.

The flash programming method for these two areas can be confirmed by the following link.
https://wizwiki.net/wiki/doku.php?id=products:wiz750sr:developers:start#flash_programming_using_wizisp_tool

The latest version of the integrated firmware for both the App and Boot areas can be downloaded via the link below, and the file name includes the string ‘_incl_Boot’, such as ‘WIZ750SRv124_incl_Boot.bin’.

I understand BOOT.BIn consist of the following files: fsbl, uboot a am not sure about what all is there in the image.ub. Does image.ub contains dts file? Actually whenever I boot linux I just copy BOOT.BIN and image.ub to sd card, and it works, without dts file. So I want to know if the image.ub contains devic etree or not ?
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