Storage

• The BIOS is stored on the motherboard.motherboard image by Ivonne Wierink from Fotolia.com
  
  Operating systems and most other programs on a computer are stored on the hard drive. The BIOS program, however, is stored on the computer's motherboard on a special BIOS chip. Even if there were no hard drive, the computer could carry out basic tasks such as initializing the keyboard and video display. Once the main operating system has booted up, it takes over control from the BIOS of most of the system's hardware.
  
  

BIOS Stored in Flash Memory

• Modern BIOS chips use flash memory, which means that settings in the BIOS can be changed and the changes will be retained when the system is restarted. This also means the entire BIOS can be replaced with an upgraded version. Manufacturers sometimes will provide an upgraded BIOS to fix bugs or take advantage of newer technology.
  
  

Accessing the BIOS

• Often, the "Delete" key provides access to the BIOS.red botton delete in macro image by Alexey Klementiev from Fotolia.com
  
  A user can access the BIOS by pressing the correct key before the operating system is loaded. The specific key can vary from manufacturer to manufacturer but is usually the delete key or one of the function keys, such as F12. Once the key is pressed, the system will not load the operating system and instead will load a BIOS menu of options.
  
  

Changing Boot Order in the BIOS

• While the average computer user will rarely need to access the BIOS, one common task handled by the BIOS is changing the boot order. The computer usually will look for startup (boot) instructions for the operating system on the hard drive. Sometimes, such as when installing or repairing the operating system, it might be necessary to boot from a CD/DVD drive or USB flash drive. Users can change the boot order within the BIOS.
  
  

Advanced Settings

• Users can change a variety of other settings in the BIOS. For example, the speed at which the processor operates can be increased (overclocked). There are also diagnostic tools within the BIOS that are helpful when troubleshooting a problem on the computer and power management settings that optimize the computer's energy usage. Manufacturers usually discourage users from changing settings in the BIOS, however, as an incorrect setting could damage the system.