Once you start linux terminal than you required Basic command for understanding for New Linux converts coming from the Windows you requred basic command for how we  work on linux.

Linux Basic system Info command 

 

1. The man command 

The man command in Linux is used to display the user manual of any command that we can run on
the terminal. It provides a detailed view of the command which includes NAME, SYNOPSIS,
DESCRIPTION, OPTIONS, EXIT STATUS, RETURN VALUES, ERRORS, FILES, VERSIONS, EXAMPLES,
AUTHORS and SEE ALSO.

# man [OPTION]... [COMMAND NAME]...
# man tail

2. who command 

Who command is show  who are login in system and show the login time and how much user login.

# whoami

3. whoami command

it show the who user login in the system root user or simple user login in the system

# who

4. date, uptime  command

This command is Show the current date and time and uptime show time and load average

# date

5. cal command 

Show this month’s calender

# cal

6. ls command 

It shoe the list of directories  of file the  am many option to show the directories  hidden files and time modification

# ls [OPTION]... [COMMAND NAME]...
# ls -a       (Hidden file)
# ls -lt       (Time modification)

7. cd command 

It is use for the change the directory of the file or move to the main directory or sub directory

# cd [directory name or path]
# cd /etc/passwd 
# cd ..         (move up directory)
# cd ../..      (move main directory)

8. pwd command

It show current working directory

# pwd

9. clear command 

This command is use linux  clear the screen or it short cut is press the Ctrl+l

# clear

10. history command

This command is show the list show many command is run on the terminal

# history

11. touch command 

This command is use create the file and create a single or more file in linux

# touch [file name]               (single file)
# touch file[1..10].txt           (more than file)

12. mkdir  command 

This command is use create the directory  single or more directory in linux

# mkdir [directory name]    (single file)
# kdir xyz[1..10]           (more than file)

13.  cat command 

This command is list the in side details in file or folder

# cat [file or directory name]

14. rm , rmdir command 

This command is remove or  delete  the file or directory empty , but if the file or directory is not empty then using   -f to remover force file or directory empty.

# rm [file name]
# rm -f [filename]           (remove no empty file)
# rmdir -r [directory name]
# rmdir -r [directory name]  (remove no empty directory)

15. cp command

This command is copy data source to destination. It is base on absolute path and relative path.

# cp [source]  [destination]
# cp /etc/passwd  /home              (absolute path)
# cp [file name]  /home              (relative path)

16. mv command 

This command is copy data source to destination. It is base on absolute path and relative path or rename the directory name.

# mv [source] [destination]
# mv /etc/passwd /home (absolute path)
# mv [file name] /home (relative path)
# mv /home/ubuntu /home/linux

17. df command 

command in Linux stands for “disk free.” It is used for checking the space available across the different file systems of your Linux system. If add the -Th for show the type of human readable form add more details -help.

# df 
# df -Th
# df -help

18. grep command 

This command is more use full for find the pattern  in file it many use to find custom  output it search live data in any order if find in revers order -r.

# grep [option] | [pattern name] 
# grep -r [pattern dir]                     (revers search)

19. reboot commnad 

This command is use for the reboot the system other method is init 6 for reboot.

# reboot 
# init 6

20. shutdown

This command is for use shutdown the system other method is init 0 it use for shurdown.

# shutdown
# init 0