Firmware eventually evolved from ROM to flash memory firmware; thus, it became easier to update and user friendly.
There are levels of firmware: BIOS, modems and video cards are usually easy to update.
Firmware also retains the basic instructions for hardware devices that make them operative.
Without firmware, a hardware device would be non-functional.
This topic is one that I often find myself explaining in more detail, and one that many people aren’t even aware that they can update their camera’s firmware, and how this may affect their digital camera.