Booting is the process of loading system files into memory to start a computer. It involves POST, BIOS, and loading essential files like IO.SYS, MSDOS.SYS, CONFIG.SYS, and COMMAND.COM. There are two types of booting: warm booting performed by pressing Ctrl+Alt+Del, and cold booting which occurs when powering on from an off state.

1. Welcome
Good Morning
Students

2. Booting of a
Computer System
Parwat kumar Shrestha
Adarsha Information Technology
Biratnagar-09

3. Objectives
By the end of the session, the Junior Computer
Technician (JCT) will be able to
 Define “Booting”
 Discuss the types of Booting
 List the steps of Booting
 Define warm booting and cold booting
 Recall the system files.

4. Definition
Booting is the process of loading
the system files (Io.sys, Msdos.sys,
command.com) in computer
memory.

5. Why is Booting Required ?
 Hardware doesn’t know where the operating
system resides and how to load it.
 Need a special program to do this job –
Bootstrap loader.
 E.g. BIOS – Basic Input Output System.
 Bootstrap loader locates the kernel, loads it into
main memory and starts its execution.

6. Booting Process
POST
B
I
O
S
IO.sys
Msdos.sys
Config.sys
If present
Command.com
Autoexec.bat
If present
C:>
ROM RAM
Power Button

7. Tasks performed at boot up

8. How Boot process occurs ?
1. Press the Power button on then the CPU begins
executing the instructions in the ROM BIOS.
2. The BIOS performs the power-on-self-test (POST).
3. If the POST tests are successful then it loads the Io.Sys
and Msdos.Sys file in RAM memory.
4. If there is Config.Sys file in boot disk, config.sys is
loaded into memory and processed.
5. Again Command.com is loaded in RAM Memory
6. After that Autoexec.bat file is loaded in RAM Memory.
It contains all of the commands that the user wants to
execute automatically every time the computer is
started.
7. As the final step in its boot process the computer
displays the Dos prompt.

9. Types of Booting
Warm Booting
 Cold Booting

10. Warm booting
 The booting which is performed from the
power on stage by pressing Ctrl + Alt+ Del
keys simultaneously
or
pressing reset button of the computer
is called warm booting.

11. Cold Booting
Booting is performed by switching on
the power from the power off stage, the
computer searches the system files and
loads them to the computer’s memory
is called cold booting.

12. Examples
 WIN95/98/ME BOOT PROCESS
 WIN2000/NT/XP BOOT PROCESS
 WINDOWS VISTA / 7 BOOT PROCESS

13. Analogies

14. Summary of the Boot Sequence
 POST
 MBR
 IO.SYS
 MSDOS.SYS
 CONFIG.SYS
 COMMAND.COM
 AUTOEXEC.BAT
 Command prompt

15. Any questions …

16. Review
 What is Booting?
 Name the system files?
 List the types of booting
 Define warm booting and cold booting.
 What is the full form of BIOS.
 What does the POST mean.

17. Assessment: Short-Answer
 What is Booting?
 List the System files of computer
 Name the types of Booting

18. Thank You