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1. LINUX ARCHITECTURE
Prof. Neeraj Bhargava
Mrs. Shubha Chaturvedi
Department of Computer Science, School of Engineering & System Science
MDS University Ajmer, Rajasthan

2. LINUX ARCHITECTURE

3. The Linux operating system's architecture
mainly contains some of the components:
• The Kernel
• System Library
• Hardware layer
• System
• Shell Utility

4. 1. KERNEL
• The kernel is a computer program at the core of a
computer's operating system that has complete control over
everything in the system. It is the "portion of the operating
system code that is always resident in memory", and facilitates
interactions between hardware and software components.
• A kernel is the foundational layer of an operating system (OS). It
functions at a basic level, communicating with hardware and
managing resources, such as RAM and the CPU. Since
a kernel handles many fundamental processes, it must be loaded at
the beginning of the boot sequence when a computer starts up.
• The kernel connects the system hardware to the application
software, and every operating system has a kernel. For example, the
Linux kernel is used numerous operating systems including Linux,
FreeBSD, Android, and others.

5. • There are some of the important kernel types
which are mentioned below:
• Monolithic Kernel
• Micro kernels
• Exo kernels
• Hybrid kernels
The Linux kernel is used numerous operating
systems including Linux, FreeBSD, Android and
others.

6. 2. System Libraries
• System libraries are special programs that help in
accessing the kernel's features. A kernel has to be
triggered to perform a task, and this triggering is
done by the applications. But applications must
know how to place a system call because each kernel
has a different set of system calls.
• Shared Libraries are the libraries that can be linked
to any program at run-time. They provide a means to
use code that can be loaded anywhere in the
memory. Once loaded, the shared library code can
be used by any number of programs.

7. 3. System Utility Programs
• It is responsible for doing specialized level and
individual activities. Utility programs that
provide the user most of the functionalities of
an operating systems.
• Utilities are software programs that add
functionality to your computer or help your
computer perform better. These include
antivirus, backup, disk repair, file
management, security, and networking
programs.

8. 4. Hardware layer
• The hardware: The physical machine—the
bottom or base of the system, made up of
memory (RAM) and the processor or central
processing unit (CPU), as well as input/output
(I/O) devices such as storage, networking, and
graphics.

9. 5. Shell
• It is an interface among the kernel and user. It can afford the
services of kernel. It can take commands through the user
and runs the functions of the kernel. The shell is available in
distinct types of OS. These operating systems are categorized
into two different types, which are the graphical
shells and command-line shells.
• There are a few types of these shells which are categorized as
follows:
• Korn shell
• Bourne shell
• C shell
• POSIX shell

10. Assignment
1. Differentiate between Linux and Unix?
2. Differentiate between Linux and Windows?
3. Discuss Advantages and disadvantages of
Linux?
4. Explain in detail Architecture of Linux?
5. What is kernel of an operating system?
6. How is operating system communicate with
kernel?
7. Is Linux Kernel or OS ?
8. Explain kernel and its types?