What is Firmware?
FIrmware is software (computer programs) stored on a eraseable, reprogrammable computer chip called 'Electrically Erasable Programmable Read-Only Memory' or EEPROM. Firmware stored on an EEPROM may comprise one or more computer programs that are not lost when the EEPROM loses electrical power. When the power is first turned on, the firmware stored on the EEPROM is accessed by a computer processor chip. The firmware is coped from the EEPROM into separate active memory (RAM) and the firmware is then executed. The programs inside the firmware aren't permanently fixed; they can be changed. This makes them different from standard Read Only Memory (ROM) whose configuration cannot be changed.
Where is Firmware Used?
Firmware is used in a lot of places today. Nearly all small personal electronic devices use firmware. There is firmware in your cell phone, in your personal data assistant (PDA) and in your MP3 player. There is firmware in your GameBoy and PlayStation Personal handheld. Your digital camera has firmware and so does your fax machine. Your car uses firmware to store the programs that control the anti-lock brakes, fuel pump, airbags, door locks, security systems, power steering system and more. Computers have used firmware for many years as boot ROM/PROM. Today, computers use a flashable EEPROM with firmware in them so that the boot programs can be modified when a problem or bug is found or when new capabilities not yet ready at product launch become ready. A USB memory key also contains firmware to instruct the on-board chip how to connect to the USB port and transfer data, but the storage memory itself is just flashable computer chip memory. ATM machines, routers, switches, firewalls and any other computerized device that needs to know what to do when it is first turned on and which might need to become smarter over time will use firmware.