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1. echoing data:
        syntax: echo name(variable).
            returns the value of the variable

2. help:
        syntax: man command
            this will give us the syntax and options available in UNIX.

3. searching a particular file:
        syntax: find -name "tools.jar" print 2>/dev/null
            searches for the file "tools.jar" based upon the name and if not found returns error msg 2 and so we redirect it using ">" to the /dev/null directory.

4. pipe symbol:
        syntax: process1 | process 2
            the pipe symbol "|" is used to provide the output of one process as the input to the other process
            eg. ls -l | wc : here 'ls -l' returns the list of files within the directory and we provide this as the input to the second process 'wc' (wordcount). thus returning the word count of the list of files .

5. tee:
        syntax: tee option filename 
                 read from standard input and write to standard output and files

6. source:
        syntax: source folder_name    
                to get the required created variables from the specified folder.

7.  ls command to list the files in the directory.
8. cat command to view the existing file.
        Syntax: cat  /etc/list.txt

9. vi command to edit a file
        Syntax: vi filename

10. Nano: Another editor to edit files.

11. mv command: to rename/move files from one location to another.
            mv oldfile newfile

12. rm command:removing files (deleting)
        syntax:  rm filename
     rmdir : removing directories
        syntax: rmdir directory

13. chmod : change file access permissions.
        eg: chmod 755 file.txt
        has a 10 digit binary code.
        400 read by owner

        040 read by group

        004 read by anybody (other)

        200 write by owner

        020 write by group

        002 write by anybody

        100 execute by owner

        010 execute by group

        001 execute by anybody

14. chown - change file owner and group



    chown [OPTION] :GROUP FILE

    chown [OPTION] --reference=RFILE FILE

15. cp - Copy files

        syntax: cp  myfile yourfile

16  cd - to navigate into files
        syntax: cd foldername/foldername/file


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