20+ must know linux commands

Basic Kali Linux Commands beginners

In this article we will learn essential linux commands that you will be using on the regular basis.Such as creating,deleting,files,directories and many more.So open your terminal:

pwd

pwd stands for present working directory.It displays our present working directory and location.

root@zeeroseven:~# pwd
/root

cd

cd(change direcroty) command is used to navigate between directories. If you want to change your present directory to some other direcroty like Downloads or anything you can do it with cd.

root@zeeroseven:~# cd Downloads
root@zeeroseven:~/Downloads# 

cd ..

Takes you one directory back.

root@seven:~/Desktop# cd ..
root@seven:~#

--help

Help is very useful command. There is a help option for every command that you have in linux. It gives all the information about the command and what you can do with it.

root@zeeroseven:~# ls --help
Usage: ls [OPTION]... [FILE]...
List information about the FILEs (the current directory by default).
Sort entries alphabetically if none of -cftuvSUX nor --sort is specified.

Mandatory arguments to long options are mandatory for short options too.
  -a, --all                  do not ignore entries starting with .
  -A, --almost-all           do not list implied . and ..
      --author               with -l, print the author of each file
  -b, --escape               print C-style escapes for nongraphic characters
      --block-size=SIZE      scale sizes by SIZE before printing them.  E.g.,
                               `--block-size=M' prints sizes in units of
                               1,048,576 bytes.  See SIZE format below.
  -B, --ignore-backups       do not list implied entries ending with ~
  -c                         with -lt: sort by, and show, ctime (

clear

clear command clears the terminal.

root@zeeroseven:~# clear

ls

ls command lists all the files and directories in our present working directory.

root@zeeroseven:~# ls
Desktop  Downloads  root

List hidden files and directories

ls -al lists all the hidden files and directories with details like file format,file permission etc.

root@seven:~# ls -al
total 156
drwxr-xr-x 22 root root  4096 Oct 18 02:35 .
drwxr-xr-x 23 root root  4096 Oct 14 05:02 ..
-rw-r--r--  1 root root     0 Oct 16 02:42 backup.txt
-rw-------  1 root root   885 Oct 16 02:21 .bash_history
-rw-r--r--  1 root root  3391 Aug 11 03:03 .bashrc
drwx------ 12 root root  4096 Oct 15 12:29 .cache
drwxr-xr-x 12 root root  4096 Oct 15 12:29 .config
drwx------  3 root root  4096 Oct 14 05:11 .dbus
drwxr-xr-x  5 root root  4096 Oct 18 02:44 Desktop
drwxr-xr-x  2 root root  4096 Oct 14 05:11 Documents
drwxr-xr-x  2 root root  4096 Oct 14 05:11 Downloads
drwx------  3 root root  4096 Oct 18 02:07 .gconf

Create files with nano

Nano: Nano is a text editor that runs inside your terminal.It is easy to use. Nano command is something that you will find using often.

root@zeeroseven:~# nano

once you press enter nano is ready to accept your input. *Note: File will be saved in your present working directory. To create file at the beginning type nano filename and press enter. nano filename

root@zeeroseven:~# nano hello.py

1. Control+o To save file.
2. Control+k To cut text.
3. Control+u To undo.
4. Control+w to searching plain text inside nano.
5. Control+x To exit nano.
6. Control+y To previous page.
7. Control+v To next page.
8. Control+k To next Line.
9. Control+p To previous line.

cat

cat command is used to view file content,creating files,merging files etc.

View content of a file with cat

root@zeeroseven:~# cat players

create new file with cat

Press Control+c to exit.

 root@zeeroseven:~# cat>animals

Delete a file

rm command is used to remove files and folders/directories. Syntax is very simple:
rm [file name that you want to delete].

root@zeeroseven:~# rm users.txt

Copy files

Copy command is easy to use. Copy command is used to make copy of files and directories. Syntax :
cp [name of the file that you want to make copy of] [name of new copy]

root@zeeroseven:~# cp users user

Create Directories or folders

Creating directories is one of the easiest task in linux. Syntax for creating directory is:
mkdir [directory name]

root@zeeroseven:~# mkdir java

We can create multple directories with a single command:

root@zeeroseven:~# mkdir java shell py

Delete Directory

Deleting directories is a little different than files.You have to supply -r argument along with rm command in order to delete a file. Syntax:
rm -r [directory that you want to delete]

root@zeeroseven:~# rm -r java

Copy Directories

Like rm command we need to supply -r argument to copy directories.
cp -r [name of the file that you want to make copy of] [name of new copy]

root@zeeroseven:~# cp -r users userscopy

Rename files with mv command

mv command is used for two purposes.We can move files from one directory to another and it will rename files or move from one name to another.

 root@seven:~# mv file.txt backup.txt

when you execute above command file.txt will be renamed with backup.txt.

View System resources with Top

Top command shows the list of processes running on your system.It gives summary of how much your system resources are being utilized.

root@zeeroseven:~# top

which

which command is used to find where the executable file is located in your file system.

root@seven:~# which firefox
/usr/bin/firefox
 root@seven:~# which ls
/bin/ls
root@seven:~# which pwd
/bin/pwd

whatis

whatis command shows the description of the command.

root@seven:~# whatis ls
ls (1)               - list directory contents
root@seven:~# whatis top
top (1)              - display Linux processes

man

It shows a manual page for just about any command you can think of. For example if you want to know more about pwd command you can check it's manual page by typing man and command name like this.

root@zeeroseven:~# man pwd

who

who command displays who is logged on to the system.

 root@zeeroseven:~# who
root     tty7         2015-10-12 01:49 (:0)
root     pts/0        2015-10-12 01:49 (:0.0)
 

cal

The cal utility displays a simple calendar in traditional format.

root@zeeroseven:~# cal
    October 2015      
Su Mo Tu We Th Fr Sa  
             1  2  3  
 4  5  6  7  8  9 10  
11 12 13 14 15 16 17  
18 19 20 21 22 23 24  
25 26 27 28 29 30 31

Also Read