The BIOS (Basic Input/Output System) is a small memory chip located on the motherboard containing data that defines the system parameters. The data may, however, contain errors (bugs). Furthermore, when new hardware becomes available, BIOS manufacturers may decide to upgrade their BIOS.
However, this is not as simple as it seems, as you may already know the BIOS is memory that persists when the PC is turned off (it would actually be very unpleasant to have to configure the BIOS each time you boot your computer...). As a result, BIOSes have evolved over to the past few years so that they can be updated.
On the earliest PCs, BIOSes were ROM chips soldered to the motherboard and were impossible to modify. Certain manufacturers were still able to offer software corrections (called patches) that were stored on the hard drive and loaded into RAM (RAM) to correct any bugs. They were only able to act, however, after the PC booted up.
BIOS manufacturers then began to sell socketed BIOSes that could be physically changed, but whose price was very high at the time.
Next came electrically programmable read-only memory, which were memory chips that could be modified using a machine that sent electrical pulses via special-purpose connectors. This type of chip programmer was rare, however, so that the operation was always relatively expensive for the user.
Most motherboards have flash memories, that can be directly modified by software. BIOSes installed on motherboards having this type of memory can be upgraded using a program called firmware, provided by the manufacturer, that replaces the old BIOS with a more recent BIOS. The problem, however, was how to obtain updates for one's BIOS (a problem that has now been resolved thanks to the Internet). These updates are available in the form of binary files containing a BIOS image that is transferred to flash memory using firmware.
Before flashing your BIOS, you have to be sure you know what the benefits are. Flashing does, in effect, allow the BIOS to be updated for various reasons (bug fixes, new features, support for new hardware), however, the improvements provided do not necessarily affect all users. Furthermore, there is no guarantee that the new BIOS itself will not have new bugs...
So, are the improvements brought by flashing the BIOS (generally described in a file accompanying the new BIOS) worth the risks incurred (small as they may be)?
If your system is working correctly and you want to flash your BIOS "just to see", in the hope of some hypothetical improvements, then it would be best not to do it. There is a very simple rule:
Any system that works correctly should only be updated for known reasons.
Flashing the BIOS changes the hardware that is being flashed, in other words, it modifies the behavior of the hardware containing the BIOS (this could be the motherboard, a video card, a SCSI card, ...), so you need to be very careful.
Guidelines to be followed: