The difference between "software" and "firmware" is mostly relative to your view point. It's another level below the stuff you work on yourself. For example ma

The difference between "software" and "firmware" is mostly relative to your view point. It's another level below the stuff you work on yourself. For example many modem modules these days have fairly powerful ARM SoCs running Linux and they also have another smaller processor running a RTOS or bare metal that does the radio stack. The whole module could be integrated into a larger device itself running Linux too (such as a payment terminal). The terminal owner will probably consider the entire terminal software as "firmware" (since it's in a device and pretty opaque to them and they likely can't update just some applications like on their PC). The developpers working on the code in the terminal will probably call what they do software and consider the stuff that goes in the modem module to be "firware" (and probably not differentiated between the Linux based and RTOS based parts of the modem). The developpers working on the Linux part of the modem will probably consider what they do to be software and the firmware to be the RTOS based stuff that runs on the baseband processor.