|
Command |
Description |
Syntax |
Sample
Output |
|
man |
To
display the manual page for a given command. |
$man
[command name] |
Shows
the help of the command |
|
who |
To
display all the users who are currently using the system. |
$who |
Display
current user details |
|
whoami |
Displays
only your details. |
$whoami |
Display
current user |
|
pwd |
Shows
current working directory. |
$pwd |
Shows
current path |
|
ls |
Shows
all the files in the current directory. ls can be used with several options. |
$ls |
List
all file at that path |
|
cd |
To
change directory. |
$cd
[directory_name] |
Change
path to directory path |
|
rm |
Removes
files. By default it does not remove directory. |
$rm
[file_name] |
Remove
directory |
|
cp |
Makes
copies of files and directories. |
$cp
[dir_of_sources] [destination] |
Make
copy of directory of source to detination |
|
mv |
Moves
files to other directory. |
$
mv [source_file] [dest_file] |
Move source to
dest path |
|
mkdir |
Creates
directory under the current working directory. |
$mkdir
[directory_name] |
Make
directory to current directory |
|
rmdir |
Removes
directory under the current working directory. |
$rndir
[directory_name] |
Remove
the directory |
|
echo |
Displays
a text or message on the screen. |
$echo
“[string]” |
Print
the string |
|
cat |
Universal
file viewer. Displays the content of a file. |
$cat
note1 |
Display
the content of mention file |
|
wc |
Count
lines, words and characters of a file. |
$wc
[file_name] |
Conut
the line byte and words of given file |
a) History of Unix and Linux
a. The
history of Unix dates back to the mid-1960s, when the Massachusetts
Institute of Technology, AT&T Bell Labs, and General Electric were jointly
developing an experimental time-sharing operating system called Multics for the
GE-645 mainframe. Multics introduced many innovations, but also had many
problems
b. Linux,
computer operating system created in the early 1990s by Finnish software
engineer Linus Torvalds and the Free Software Foundation (FSF). While still a
student at the University of Helsinki, Torvalds started developing Linux to
create a system similar to MINIX, a UNIX operating system.
b) Kernel
of an Operating System
· It
is the core that provides basic services for all other parts of the OS. It is
the main layer between the OS and underlying computer hardware, and it helps
with tasks such as process and memory management, file systems, device control
and networking.
c) Multi-Tasking
OS
· The
multitasking OS refers to a logical extension of the multiprogramming operating
system, which allows users to run many programs simultaneously. It enables a
user to complete multiple computer tasks at the same time
d) Multi
User OS
· A
multi-user operating system is an operating system that allows multiple users
to access underlying hardware resources simultaneously. Multiple users access the
operating system with the help of many terminals connected to a network. The
objective of a multi-user operating system is time-sharing and batch processing
