ROM BIOS is no longer software and hardware separate from hard disk.
Since the factory release, the ROM chip has integrated programs and instructions into one piece. They can no longer be easily separated. A device that integrates software into such hardware is called a FIRMWARE. So the BIOS is firmware.
Programs in the BIOS
It is well known that a BIOS is a set of programs built into a ROM chip. There are four types of programs that can be used to differentiate between the functions of a computer, from the time it was started to the time it was launched until the operating system was launched.