CORE OF UNIX OPERATING SYSTEM. A WONDERFUL AND CONCEPTUAL SLIDE DESIGNED BY ME. YOU CAN READ AND UNDERSTAND IT.

2.  NAME : NARENDRA MOHAN MISHRA
 DEPARTMENT : INFORMATION
TECHNOLOGY

3.  UNIX is basically a simple operating system, but you have to be a genius to
understand the simplicity.
 THE MAN WHO IS DEVOTED TO DEVELOPE UNIX WITH UNIX DEVELOPING
MEMBER.
 Dennis MacAlistair Ritchie
 Ken Thompson
 Douglas McIlroy
 Joe Ossana
UNIX
Developed in BELL LAB [1969-1972]
47 Year Ago

4. Getting Started ARCHITECTURE OF UNIX SYSTEM
KERNEL
SHELL
FILES &
DIRECTORIES
The Kernel is the heart of the
operating system . It interacts
with Hardware.
The Shell is the utility that
processes our request when
we fire command.
All data in UNIX is organized
into files . All files are
organized into directories .
These directories are
organized into a tree-like
structure called the file

5. Monolithic Kernel
Micro Kernel
Hybrid Kernel
Nano Kernel

7. A μkernel IS A PICE OF SOFTWARE OR EVEN CODE
THAT CONTAINS THE NEAR-MINIMUM AMOUNT OF
FUNCTIONS AND FEATURES REQUIRED TO
IMPLEMENT AN OPERATING SYSTEM.
IT PROVIEDS THE MINIMAL NUMBER OF
MACHENISMS.
JUST ENOUGH TO RUN THE MOST BASIC FUNCTIONS
OF A SYSTEM, IN ORDER TO MAXIMIZE THE
IMPLYMENTATION FLEXIBLITY.
SO IT ALLOWS FOR OTHER PART OF THE OS TO BE
IMPLEMEMTED EFFICIENTLY SINCE IT DOES NOT
IMPOSE A LOT OF POLICIES.

8. HYBRID KERNEL IS A KERNEL ARCHITECTURE
BASED ON A COMBINATION OF μkernel and monolithic
kernel architecture used in computer OS.
This kernel approach combines the speed and simpler
design of Monolithic Kernel with the modularity and
execute safety of μkernel.
 A Hybrid kernel runs some services in the kernel space
to reduce the performance overhead of a traditional

9. A NANOKERNEL is a small kernel that offers Hardware
Abstraction, but without system services.
A Hardware Abstraction Layer(HAL), which forms the
lowest level portion of a kernel.
Occasionally ,the term NANOKERNEL is used to
described a kernel that supports a nanosecond clock
resolution.
The term NANOKERNEL first appeared in the paper ” The
KeyKOS NANOKERNEL Architecture”. The KeyKOS

10. PROPERTY KERNEL USES

11. Shell gathers input from user and executes programs based on that input. When a
programme finished executing, it displays that program’s output.
A shell is an environment in which we can run our commands, programs, and shell scripts .
There are different flavors of operating systems. Each flavor of shell has its own set of
recognized command and functions.
 In UNIX there are two major types of shell :
A. The BOURNE shell ($)
B. The ‘C’ shell(%)
Bourne
shell
Bourne
shell(sh)
Korn
shell(ksh
)
Bourne
Again
shell(bash)
POSIX
shell(sh)
‘C’ shell
’C’
shell(csh)
TENIX/TOPS
C shell(tcsh)

12. From todays PPT Presentation, we are able to know
about Unix core feature as well as UNIX fully
Architecture. That’s helps to learn more about UNIX.
If UNIX could present the same face, the capabilities,
on machines of many different types, it could serve
as a common software environment for all of us.

13. BOOKS OWN ANALYSIS NOTES WEBSITE
MODERN OPERATING
SYSTEM[TANANBUM]
BASIC OS ANALYSIS WIKIPEDIA : UNIX
ARCHITCTURE
UNIX CONCEPT AND
APPLICATION[SUMITAB
H DAS]
UNIX/LINUX OWN
ANALYSIS
TUTRIAL POINT :
UNIX,LINUX
CDAC LINUX[DAVID
NASH]
KERNAL ANALYSIS TECHOPEDIA : KERNEL
WWW.DIFFEN.COM [FOR
Referred books to knowledge