Simple questions: What is firmware? What does it do?

Firmware… you've probably heard about it at some point. It sounds like a weird German name, doesn't it? What is firmware? What is the meaning of this term? What does firmware do? How does firmware work? Surely, its purpose is not just to confuse you. As you will learn in this tutorial, the firmware is critical when it comes to hardware devices of all kinds, from smartphones to smart TVs, to washing machines and other devices. To clear things out and help you become more knowledgeable, in this article we will explain all the important things you need to know about firmware. Let's get started:

What is firmware? The definition

Firmware is a small piece of software that makes hardware work and do what its manufacturer intended it to do. It consists of programs written by software developers to make hardware devices "tick." Without firmware, most of the electronic devices we use daily wouldn't be able to work. They would not do anything.

For example, did you know that a simple traffic light has firmware on it? Yes, it does, and the firmware is what tells it to change the lights at regular intervals. Without firmware, the traffic light would be just a "stupid" mast, placed on the side of the road, doing nothing except looking bored. For less sophisticated hardware devices, like traffic lights, washing machines, card machines, surveillance cameras, TVs and so on, the firmware is all the software on them, and it also acts as an operating system, controlling everything about that device’s functioning.

To make things even clearer, let's take another example: a computer motherboard without firmware would not know how to detect the hard drive or the video card that is found inside your computer. If your drives didn't have firmware embedded in them, they wouldn't know how fast to spin or when to stop. A wireless network card wouldn't know how to use a particular radio frequency.

For more complex hardware, like smartphones, tablets, smart TVs, smartwatches and so on, the firmware is the middleman between the hardware and the operating system. On such devices, the firmware contains only the necessary instructions for the hardware to operate with the operating system that is installed on the device. For example, on a Samsung Galaxy smartphone with Android, the firmware on the smartphone allows the hardware to communicate correctly with the Android operating system and do what is requested by the user.

We often tend to think about a hardware device as a device that is just hardware. And we assume that it just works by itself. However, almost none of the modern hardware devices would work without this particular software that's written directly onto them.

Say after me: Firmware!!! Now it sounds like something magical, doesn't it?

Where is the firmware stored?

We now know that firmware is software written directly into our hardware devices. But how exactly is it stored on a device? Firmware is usually stored in special types of memory, called flash ROM. ROM is the acronym for Read Only Memory and this kind of memory should only be written once, usually by the manufacturer of the hardware that we are using. A ROM memory is needed for any electronic device because it must hold data permanently, even when the device is turned off or when there is a power outage. You can't produce a hardware device that forgets its firmware, as it would cease to function once you pull out its source of energy.

But then again, flash ROM memory is a rewritable ROM memory because, while it is initially written by the hardware manufacturer, it can be rewritten afterward. Of course, you can write new firmware onto a hardware device. However, you can do it only with a proper firmware updating tool, that is specially designed to work for that hardware device.

What kinds of firmware are there?

There is as much variety in firmware as there is in hardware devices. There's firmware in computer motherboards (it's called BIOS or UEFI), there's firmware in hard disks, solid-state drives (SSDs), CD/DVD/Blu-Ray drives, there's firmware in network cards, routers, access points, range extenders, there's even firmware in your gaming mouse and keyboard. These are just some examples that are related to computers.

You should remember that firmware exists in most of the devices that do something useful, like your TV, washing machine, the ATMs of your bank, or even in your car. You name the device; it probably wouldn't work without its firmware.

What is the difference between firmware and drivers?

We have another article that explains in detail what drivers are. You should read it: Simple questions: What are drivers and why do you need them?.

While both have the role of allowing hardware to do what is requested of it, one important difference is that firmware is stored on the hardware device itself while drivers are installed inside the operating system. Also, firmware can start on its own and do what it is programmed to do while drivers must be run by the operating system. The biggest difference between the two is that the firmware tells the devices what they should do, while the driver tells the operating system how to communicate with the same devices.

Can the firmware be upgraded?

Many manufacturers release regular updates for the firmware found on their hardware devices. They also provide the necessary software tools to write the new firmware onto those devices. However, each manufacturer can choose whether it releases a new firmware for an individual device, or not. For instance, most computer parts manufacturers develop and provide customers with new firmware and the corresponding firmware updaters, at least for a few years after the device was launched.

To give you an example, the manufacturer of your motherboard can release new firmware updates when it wants to include new features, support new processors or RAM, or when it wants to solve specific problems with your hardware.

Any manufacturer can choose to deliver new firmware for its devices: a router can receive a firmware update that enhances its stability, a DVD writer can learn how to burn new types of discs and so on.

As far as where from to get new firmware, that depends on your hardware device manufacturer. Usually, you can find new firmware (if available) on your device's support website. Look for a download page, download your new firmware and be careful to follow the upgrade documentation offered by the device manufacturer.

Writing new firmware on your device is a treacherous job and, if done incorrectly, can render your device useless. Forever! Like a brick! That's why some people tell you that you bricked your device: you just ruined its firmware, and it can no longer function as it was intended to.

If you need some help with updating the firmware on your devices, we recommend the following tutorials:

The problem with smartphones, tablets, smart TVs and Android “firmware”

Android smartphones and mobile devices have conquered the world, and many users want to update the “firmware” on their devices, install custom ROMs and so on. The problem is that most people now incorrectly use the term firmware when they refer to smartphones and other mobile devices. Because of that, we want to explain the technicalities of firmware, when referring to smartphones and mobile devices, so that you get things right:

  • The term firmware, especially when speaking about devices with Android, has been incorrectly expanded in popular culture to encompass all the software on those devices. Android “firmware" now means the firmware plus the Android operating system on top of it.
  • You also encounter the term Custom ROM. ROM doesn’t mean, in this case, the Read Only Memory where the firmware is stored in the smartphone’s hardware. Custom ROM means a custom operating system image that also includes the firmware necessary for the smartphone to work. So you get two things in the ROM of a smartphone: the firmware, that is the same as in the definition we shared earlier and the operating system on top of the firmware.
  • When you buy a smartphone, it comes with a “stock ROM” or “stock firmware.” This refers to the preinstalled firmware and operating system.The “stock ROM” is provided by the manufacturer of the smartphone (if you have bought it unlocked) or by the mobile operator where you have a subscription (if you bought a locked smartphone). The mobile operator uses the “stock ROM” that is offered by your smartphone’s manufacturer and modifies it according to their interests, resulting in a new “stock ROM” that is found only on the smartphones that are sold by that mobile operator.

The same goes for smart TVs, for tablets and other mobile devices with Android.

Conclusion

And now you know what firmware is, what it does and where it's found. Was our explanation good enough? Do you understand this concept? Are you still confused by Android “firmware"? Don't hesitate to use the comments form below and let us know.