Booting the Computer

Basically, the process of starting your computer is called booting. In fact, the process of loading DOS system files into the computer's memory (RAM) from a disk (e.g floppy disk or hard disk) is known as booting.
Once the system files are loaded, DOS prompt appears on the screen and your computer is ready to receive and interpret the commands

Types of booting
Booting of the computer can be performed in two ways. which are :
1. Cold Boot
2. Warm boot

1. Cold Boot :
When a computer is turned on, the computer reads its RAM space and searches for the DOS system files from disk drives (floppy drives A: and hard disk drive C:). As soon as it finds the system files, those files are brought into computer's memory from A: or from C: drive. This is known as Cold Boot    
So, when your computer is at Off state and you put on the power switch of the computer, the computer follows the cold boot process.

2.Warm Boot :
If you are working with your computer and you wish to reboot the computer, you press CTRL, ALT and DEL keys at the same time, computer stays powered On during the process and searches for DOS system files and loads these files into the RAM. This is known as Warm Boot.
So, when your computer is at On state (already started) and again you want to restart it, press the keys CTRL, ALT and DEL at the same time ; the computer follows warm boot process. In warm boot process, ROM instructions are not executed and RAM space is not  read.