MS DOS is an operating system created by Microsoft that uses a layered structure. Each layer has a specific functionality, and changes to one layer do not affect the others. This makes the system easier to create, maintain, and update. However, the boundaries between layers in MS DOS are not sharply defined, and specifications sometimes overlap between layers.

1. MS DOS Structure
Dr. Amar Nath
AP SLIET Longowal

2. MS DOS
• MS-DOS is an operating system created for
personal computers. It was developed by
Microsoft.
• It is a classic example of an operating system
with a layered structure. MS-DOS operating
system is split into various layers and each of
the layers have different functionalities.

5. • Layering provides a distinct advantage in the MS-
DOS operating system because all the layers can
be defined separately and interact with each
other as required.
• Also, it is easier to create, maintain and update
the system if it is done in the form of layers.
Change in one layer specification does not affect
the rest of the layers.
• However, the layers in MS-DOS are not that
sharply defined, and the layer specifications often
bleed into each other.

17. The part of the operating system that receives
and executes operating system commands. Every
operating system has a command processor. When the
command prompt is displayed, the command
processor is waiting for a command.
After you enter a command, the command processor
analyzes the syntax to make sure the command is valid,
and then either executes the command or issues an
error warning. For operating systems with a graphical
user interface, the command processor
interprets mouseoperations and executes the
appropriate command.
Command Processor

18. Most computers are configured to boot from the
hard drive. With a simple change to the system
BIOS, you can tell your system to boot from a
floppy disk.
This is useful if you are having problems with your
operating system, if you have been infected with
a virus or having other problems booting your
computer. All Windows systems allow you to
create a bootable floppy just for these types of
situations.
Booting from floppy and Hard
Disk (HD)