Normally, we are all clear about the difference between hardware and software in computer systems: the hardware is the part of the physical device and its peripherals, everything that can be touched (and, hence, its name as "hard"), while the software is the intangible program that makes the hardware, the operating system and the programs.
But what about the firmware? It is the rarest and least known piece, which together with the previous two forms a triad that allows the operation of computer systems.
Controlling the hardware
We could define very quickly the firmware like that software who works directly in contact with him hardware. If we look for a more encyclopedic definition, we will say that it is the software which controls electronic circuits at a low level in any device.
Indeed, the firmware It is not exclusive to computers, but we also have it in our DVD / Blu-ray players, televisions and multiple formats of electronic devices, even cars have firmware.
The best known: your computer's BIOS
The firmware most famous, however, is the BIOS (Basic Input / Output System), found on PC computers. This element is the first one that starts when we press the start button of the computer, and its tasks begin by checking the hardware present in the PC, and loading the operating system with which we will later work.
The BIOS has a user interface that allows us, for example, to choose from which storage unit we will start the operating system (internal hard disk, DVD disk in the subsequent reader, USB key, from the network, ...), adjust date and time, or monitor the CPU temperature.
Faced with events such as, precisely, excess heat on the computer's microchip, the BIOS is responsible for carrying out an emergency shutdown. It also manages the so-called “interruptions”, events caused by the hardware that cause the software take action and act accordingly.
For example, pressing a key on the keyboard triggers an interrupt that informs which key was responsible and allows the operating system to draw a letter or other symbol on the screen, or to carry out a specific action.
The firmware is upgradeable
The successor to the BIOS is the UEFI, which brings extra functionality to the BIOS such as graphical menus and modular design to add new elements in the future.
Update firmware of a device is a delicate task, but this does not mean that it is necessarily difficult; many devices provide an update system by software that downloads the latest version of the firmware from Internet.
Photos: iStock - MMassel / Yuri_Arcurs
