Read through the forum entries first.
Firmware is the software installed in the hardware to help it operate, also it has to be updated from time to time to cover latest specs, media types, formats, etc.
Humax would normally release this, although some people make their own .. and are generally known as "hacked firmware" These are not bad .. sometimes better than manufacturers own, and are often modifications to enable a disabled feature, or change look/feel of menus, etc.
See how you get on.