Firmware

is a form of microcode or program embedded into hardware devices to help them operate effectively. it gives the basic machine instructions that allow the hardware to function on a device.

Types of Firmware

• Low-level firmware; it is stored in non-volatile memory chips like read-only memory (ROM) and it can’t be updated or rewritten. devices/ gadgets that use low-level firmware make use of One-time programmable memory.
• High-level firmware; High level firmware does  and is generally more complex than low-level firmware. This type of firmware is installed within flash memory chips, it allow updates.
• Subsystem firmware; it is semi-independent devices of an embedded system. it can be updated and is more complex than low-level firmware.