What is Firmware?
Firmware is a program written to the non-volatile memory of a hardware device. Volatile memory is a form of static random access memory in which contents are saved when the hardware device is turned off or loses external power.
Firmware is installed directly into a piece of hardware during the manufacturing process. It is used to run user programs on the device and can be thought of as the software that allows the hardware to run.

Hardware manufacturers use embedded firmware to control the functionality of various systems and hardware devices, just as a computer's operating system controls the functionality of software applications. Firmware can be written to read-only memory (ROM), erasable programmable read-only memory (EPROM), or flash memory.
American computer scientist Ascher Opler coined the phrase firmware in a 1967 issue of the publication Datamation. He used the term to describe a type of firmware that lies between hardware and software.
Today, embedded firmware exists in everything from smartphones to Internet of Things (IoT) devices. It is often included in devices that are not traditionally considered capable of being controlled by a computer.
Why are firmware updates important and how do they work?
Firmware updates are often released to fix bugs, prevent firmware hacks, implement new features, improve security, or interact with new media. Firmware updates include code that tells the hardware how to operate in a new or modified way.
Some examples of firmware updates include:
- CD recorders are capable of recording a new type of disc.
- The router received an update that improved its performance and stability.
- A motherboard manufacturer releases a BIOS update that allows the motherboard to support a new processor. BIOS is motherboard software.
Some Internet-connected devices regularly check for new firmware and automatically download and install it. Other device manufacturers require users to visit the manufacturer's website to manually download and install firmware updates. Manufacturers release updates on a regular basis.
Firmware update frequency will vary by device. Firmware in smart bulbs may not need to be updated regularly. However, the firmware on the smart thermostat may need to be periodically updated to maintain compatibility with smartphone operating system updates. Smartphones often automatically upgrade their firmware along with software updates so that the phone stays functional and users do not have to manually update firmware versions that coincide with software updates. The process of remotely updating firmware by downloading upgrades from the service provider is sometimes called over-the-air firmware.

Many electronic devices also require the device to stay on while updating the firmware so that the update is not corrupted. Corrupting your device's firmware may affect some devices or cause them to malfunction.
Types of firmware
There are many types of technology-specific Firmware, but in general all firmware can be sorted into three categories based on the level of hardware integration.
- Low level firmware. Low-level firmware is considered an intrinsic part of the device's hardware. It is often stored on unstable, read-only chips such as ROM and therefore cannot be rewritten or updated. Devices containing low-level firmware have one-time programming memory.
- High level firmware. High-level firmware allows for updates and is often more complex than low-level firmware. In computers, high-level firmware resides on flash memory chips.
- Subsystem firmware. Subsystem firmware is often part of an embedded system. It is similar to high-level firmware in that it can be updated and is more complex than low-level firmware. An example is a server's power subsystem, which is a piece of server hardware that functions semi-independently of the server.
Firmware applications
Firmware is found in many types of computing devices, including complex devices and those not typically considered computing devices. Some real-world firmware applications include:
- Personal computer. A personal computer's firmware – BIOS or Unified Extensible Firmware Interface (UEFI) – is embedded on a small memory chip on the computer's motherboard. Computer peripherals, such as graphics and video cards, also contain firmware.
- Storage device. USBs, hard drives, and other portable storage devices contain basic firmware that allows them to work with computers.
- Mobile devices. Cell phones, tablets, laptops, and other mobile devices all contain firmware that allows the hardware to work with various software.
- Car. Cars contain many embedded systems, sensors, and small computers containing firmware that allow them to perform specified tasks.
- Household appliances. Dishwasher and washing machine are among the devices that contain firmware. Firmware that helps the machine communicate with the computer is used to configure the machine's settings and control its operations.
- Smart cards. Smart cards have instructions embedded in a chip that provide basic card functionality as well as authentication and encryption.
Difference between firmware and software
Although some people consider firmware to be a type of software, there is still a difference between these two concepts.
Firmware
Firmware is software that provides basic machine instructions that allow the hardware to operate and communicate with other software running on the device. Firmware provides low-level control over the device's hardware. For this reason, it is sometimes called “software for hardware”. Another distinguishing feature is that firmware is often not designed to be user-friendly.
Software
Software is designed for user interaction to complete specific tasks. It sits on top of the firmware, is abstracted from the hardware, and uses the firmware to communicate with the underlying hardware. Software is more complex and not tied to the underlying hardware.
Examples of software include computer programs such as operating systems. Word processing, online meeting, and music listening applications are also examples of software. A software program can usually be changed without replacing the hardware component, while firmware usually cannot.
Firmware embedded in flash memory chips can be updated more easily than firmware written to ROM or EPROM. As flash memory plays a larger role in the enterprise, administrators must learn about flash memory types and their use cases.
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