What Is POST?
The full form of POST is “Power On Self Test”. This test starts just after the switch on your computer. A predefine amount of power supply to the all parts or devices of the computer and wait for a replay of the corresponding devices.
By this method computer meets the necessary system requirements and check the health of the hardware, before starting the boot process. After passing the POST, computer start the boot process with a single beep. This sound is known as booting sound. However, if the computer fails the POST, the computer will either not beep at all or will generate a specific beep code, which tells the user the source of the problem.