BIOS and CMOS

Computer start up order

=>Turn on

=>BIOS (Basic Input/Output System)

     -Checking hardware and initializing it

     -Show error if some hardware isn't working

     -Boots the devices in order.

     -ROM chip (Read Only Memory) can't write to it.

=>Boot-up OS HDD

CMOS (Complementary Metal Oxide Semiconductor)

-Works together with the BIOS.

-Allows you to change settings because it is writable.

-Stores the date and time, device boot order, etc.

-RAM chip so it has working memory, if power is cut the settings are lost. To prevent this there is a battery which keeps the CMOS from losing power and forgetting the changes. The battery charges while the computer is on.

Peripheral devices
a device that plugs into the outside of the computer
examples:
-keyboard (input)
-mouse (input)
-headphones (output)
-usb (input and output)
-monitor (output)
-microphone (input)