Basic Linux Commands You Should Know
The real power of Linux lies in the terminal. With the correct Linux command, you can tweak, configure or change any aspect of your system.
Learning Linux has become synonymous to learning Linux commands and rightly so. Because you can use Linux entirely through commands and do so very effectively.
On Linux Handbook, you can find numerous commands explained with examples. But they are scattered across the website and it won’t be easy for you to find it.
This is why I created this Linux commands list that is more structured and organized. I have grouped the common Linux commands in categories. Even if you are absolutely new to Linux, you can start learning the commands by following their examples.
BASIC FILE AND DIRECTORY OPERATIONS
Learn to list files in a directory with ls command
Learn to copy a file with cp command
Learn to rename files with mv command
Learn to change directories with cd command
Learn to create directories with mkdir command
Learn to remove files and directories
FILE VIEWING COMMANDS
To view the contents of a file in Linux, you can use:
Cat command to view files entirely in terminal
Less command to view files one page at a time
Head command to view the first few lines of a file
Tail command to view the last few lines of a file
KNOW THE FILE PROPERTIES
Every file and directory has attributes like size, ownership, permissions etc. These Linux commands allow you to see the file attributes and change them.
File command allows you to identify the type of a file
With touch command, you can change the timestamps
Change file permissions with chmod command
Change group ownership with chgrp command
Count number of lines, words with the wc command
Know the file and directory size with du command
FILE TEXT MANIPULATION
Manipulating the text of a file to get what you want. Here are the commands:
Grep command to find matching lines in files
Cut and paste commands to treat text as columns
Tr command converts characters
Sort command lets you sort lines in text file
Tee command to copy the file and see its output simultaneously
Expand command converts tabs to spaces
USER ACCOUNT MANAGEMENT
Creating and managing users is an important job that you should not take lightly.
Add new users with useradd command
Modify existing users with usermod command
Delete existing users with userdel command
Also learn the concept of user ID (UID)
GROUP MANAGEMENT
Group management is another important task for a sysadmin.
Add new groups with groupadd command
Delete existing groups with groupdel command
Modify existing groups with groupmod command
Change group ownership of files with chgrp command
MANAGE AND MONITOR SYSTEM
Keep an eye on your system usage with these commands:
Check disk space with df command
Check memory usage with free command
Shutdown command in Linux
Use lsof command to find opened files by a process or user
Create incremental backups with rsync command
Check running processes with ps command
BASIC NETWORKING COMMANDS
Here are some basic commands related to networking:
Use dig and nslookup commands to get DNS information
Use ping command to check if remote host is up
Use curl command to download information from network
Use scp command to copy files between remote hosts
AWK Command Guide
AWK is a complete tool for manipulating every aspect of text in Linux
SED Command Guide
Sed is stream editor and like AWK, it is used for editing text on fly in Linux
SSH Command Guide
SSH is one of the essential tools for accessing and managing remote Linux systems
Very useful reminders. Thank you very much Abisheck.
In system management I would have added APT for updating , upgrading and installing/removing software packages.
Thanks for the suggestion. The page is evolving and I’ll add more commands to this page as we cover those commands.
chrone tab
Great list of commands,
but users don’t worry one does not NEED any of them
there just SOOO USEFUL for many things
That’s true, Mark.
simple and organisation is straight forward
then there are occasions when you launch say firefox from menu and system says – already running , shutdown and re-start or kill.
You kill processes by getting their PID number
to list $ps -ef
then to kill say firefox with pid 27342
its $ kill -9 27342
or just, $ killall -9 firefox
had a quick scan , xkill is a simple but useful command when prg freezes and won’t respond to clicking x in top right. simply type xkill as user ($) and put xkill curzor over gui of program and left click
Thank you Andy. I have the laptop freeze on Firefox various times a day and have to force reboot the machine. This most probably is the best command for me. Regards
Chris
Nice list but imho u missed out lsof and ps
Thanks for the feedback. I’ll add them when I have covered them in detail.