Your system BIOS (Basic Input/Output System) is what's used when your computer is turned out...it scans for bootable devices such as a hard drive or Operating System CD, detects available operating systems, and prepares the system for the chosen OS (in most cases Windows) to launch.
The BIOS settings entail things such as the current time, support for various services (such as Plug-n-Play), boot order (do you want it to check for a bootable CD, a specific hard drive, etc), displays system stats such as the temp of the CPU and fan speeds, if applicable, etc.
Under normal circumstances you shouldn't have to change the settings. Situations you would include swapping out hard drives or wishing to boot to a bootable CD (such as the Windows CD). Of course there are others, but those are the usual two.
To change settings you'd have to access your system BIOS. This is done by pressing a select key or key combination (that varies by computer and BIOS version) during boot. (Before the Windows boot screen comes up.) You can either ask here what key it is you need to press, check your owner's manual, or watch the BIOS screen when it's displayed each time you start your computer. (It will either show the standard black screen with specs, or usually your PC manufacturer's screen. At the bottom it will say 'press key' to enter setup.)
Hope this helps,
John
P.S. I deleted your duplicate post in the ''How often do you change your BIOS settings?'' thread to avoid crossover. Also, is you have technical questions, remember to use the applicable Cnet forum...this one is for responses to the polls and questions are generally overlooked.
What exactly are Bios settings, and when should one mess with them. And how does one change the Bios setting. Your answer will be greatly appreciated. Thanks.

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