You can help to improve this page by adding explanations for the different firmware types below.
See also firmware_image_names and merge both pages into one.
Previously know as trx image, sysupgrade is designed to be flashed from OpenWrt/LEDE itself 1).
Designed to be flashed by the bootloader flasher or stock firmware flasher 2)
Usually first part of a multi-stage installation, this type of firmware can be loaded from an arbitrary location and is self-contained in memory. This is like a Linux LiveCD. 3)
This firmware contains a regular ext4 Linux partition. Mostly used in x86 and x86_x64 systems.
This firmware contains a type of partition that is compressed and mounts read-only. All modifications (file edit, new files, deleted files) are committed to an overlay.
Only the root filesystem of LEDE
Designed to be loaded from tftp server. Device in recovery mode?
These are raw binary data of the firmware file
These are compressed images
SDK Toolchain for compiling single userspace packages 6)
To build custom images without compiling 7)
Linux kernel for build 8)