The BIOS ( B asic I nput / O utput S ystem) is a small memory on the motherboard, the data define the parameters of the system. They may nevertheless contain errors (bugs). In addition, with the advent of new hardware BIOS manufacturers may decide to update their BIOS.
However, this is not so simple as it seems, because as you may know the BIOS is a memory that persists when you turn off the PC (it would be very unpleasant effect need to configure the BIOS each time you start the computer ...). Thus, the BIOS has evolved in recent years to be updated. On the first PC were the BIOS ROMs soldered to the motherboard;, so you can not change them. However, some manufacturers offered software patches (called patches ) that were stored on the hard disk and loaded into memory (RAM) to correct any bugs. However, they could not act until after the boot the PC. builders BIOS then sold insertable BIOS supports, which can be changed materially, but the price was very high at the time. Then came the advent of Electronically programmable memories , that is to say, a memory that can be modified by a machine sending electrical pulses provided by connectors therefor. This type of controller chip was rare, however, so that the operation was still relatively expensive for the user. Most motherboards include flash memory , which can be modified by software. BIOS located on motherboards with this type of memory can be updated (the term "upgrade" is sometimes used, Frenchified word from the English verb " to upgrade ", which means update ) through a program called firmware provided by the manufacturer, to enable the replacement of the old BIOS with a newer BIOS. However, the problem is the updates to the BIOS (problem now solved thanks to the Internet) to obtain. These updates are available as a binary file containing a BIOS image, which will be transferred to the flash memory through firmware. Flashing the BIOS is a BIOS update by software , it is ie replacement of the old version of BIOS through a program.