Essential Unix Commands Last Updated : 04 Apr, 2024 Comments Improve Suggest changes Like Article Like Report Unix commands are a set of commands that are used to interact with the Unix operating system. Unix is a powerful, multi-user, multi-tasking operating system that was developed in the 1960s by Bell Labs. Unix commands are entered at the command prompt in a terminal window, and they allow users to perform a wide variety of tasks, such as managing files and directories, running processes, managing user accounts, and configuring network settings. Unix is now one of the most commonly used Operating systems used for various purposes such as Personal use, Servers, Smartphones, and many more. It was developed in the 1970's at AT& T Labs by two famous personalities Dennis M. Ritchie and Ken Thompson. You'll be surprised to know that the most popular programming language C came into existence to write the Unix Operating System.Linux is Unix-Like operating system.The most important part of the Linux is Linux Kernel which was first released in the early 90s by Linus Torvalds. There are several Linux distros available (most are open-source and free to download and use) such as Ubuntu, Debian, Fedora, Kali, Mint, Gentoo, Arch and much more.Now coming to the Basic and most usable commands of Linux/Unix part. (Please note that all the linux/unix commands are run in the terminal of a linux system.Terminal is like command prompt as that of in Windows OS)Linux/Unix commands are case-sensitive i.e Hello is different from hello.Basic Unix commands: Table of Content File System Navigation Unix CommandFile Manipulation Unix CommandProcess Management Unix CommandText Processing Unix CommandNetwork Communication Unix CommandText Editors in UnixFile System Navigation Unix CommandCommand Description Example cd Changes the current working directory. cd Documents ls Lists files and directories in the current directory. ls pwd Prints the current working directory. pwd mkdir Creates a new directory. mkdir new_folder rmdir Removes an empty directory. rmdir empty_folder mv Moves files or directories. mv file1.txt Documents/ File Manipulation Unix CommandCommand Description Example touch Creates an empty file or updates the access and modification times. touch new_file.txt cp Copies files or directories. cp file1.txt file2.txt mv Moves files or directories. mv file1.txt Documents rm Remove files or directories. rm old_file.txt chmod Changes the permissions of a file or directory. chmod 644 file.txt chown Changes the owner and group of a file or directory. chown user:group file.txt ln Creates links between files. ln -s target_file symlink catConcatenates files and displays their contents.cat file1.txt file2.txtheadDisplays the first few lines of a file.head file.txttailDisplays the last few lines of a file.tail file.txtmoreDisplays the contents of a file page by page.more file.txtlessDisplays the contents of a file with advanced navigation features.less file.txtdiffCompares files line by line.diff file1.txt file2.txtpatchApplies a diff file to update a target file.patch file.txt < changes.diffProcess Management Unix CommandCommand Description Example psDisplays information about active processes, including their status and IDs.ps auxtopDisplays a dynamic real-time view of system processes and their resource usage.topkillTerminates processes using their process IDs (PIDs).kill <pid>pkillSends signals to processes based on name or other attributes.pkill -9 firefoxkillallTerminates processes by name.killall -9 firefoxreniceChanges the priority of running processes.renice -n 10 <pid>niceRuns a command with modified scheduling priority.nice -n 10 commandpstreeDisplays running processes as a tree.pstreepgrepSearches for processes by name or other attributes.pgrep firefoxjobsLists active jobs and their status in the current shell session.jobsbgPuts a job in the background.bg <job_id>fgBrings a background job to the foreground.fg <job_id>nohupRuns a command immune to hangups, with output to a specified file.nohup command &disownRemoves jobs from the shell's job table, allowing them to run independently.disown <job_id>Text Processing Unix CommandCommand Description Example grepSearches for patterns in text files.grep "error" logfile.txtsedProcesses and transforms text streams.sed 's/old_string/new_string/g' file.txtawkProcesses and analyzes text files using a pattern scanning and processing language.awk '{print $1, $3}' data.csvNetwork Communication Unix CommandCommand DescriptionExamplepingTests connectivity with another host using ICMP echo requests.ping google.comtracerouteTraces the route that packets take to reach a destination.traceroute google.comnslookupQueries DNS servers for domain name resolution and IP address information.nslookup google.comdigPerforms DNS queries, providing detailed information about DNS records.dig google.comhostPerforms DNS lookups, displaying domain name to IP address resolution.host google.comwhoisRetrieves information about domain registration and ownership.whois google.comsshProvides secure remote access to a system.ssh username@hostnamescpSecurely copies files between hosts over a network.scp file.txt username@hostname:/path/ftpTransfers files between hosts using the File Transfer Protocol (FTP).ftp hostnametelnetEstablishes interactive text-based communication with a remote host.telnet hostnamenetstatDisplays network connections, routing tables, interface statistics, masquerade connections, and multicast memberships.netstat -tulnifconfigDisplays or configures network interfaces and their settings.ifconfigiwconfigConfigures wireless network interfaces.iwconfig wlan0routeDisplays or modifies the IP routing table.route -narpDisplays or modifies the Address Resolution Protocol (ARP) cache.arp -assDisplays socket statistics.ss -tulnhostnameDisplays or sets the system's hostname.hostnamemtrCombines the functionality of ping and traceroute, providing detailed network diagnostic information.mtr google.comSystem Administration Unix CommandCommand Description Example df Displays disk space usage. df -h du Displays disk usage of files and directories. du -sh /path/to/directory crontab -e Manages cron jobs, which are scheduled tasks that run at predefined times or intervals. crontab -e Text Editors in UnixText EditorDescriptionExampleVi / VimVi (Vim) is a highly configurable, powerful, and feature-rich text editor based on the original Vi editor. Vim offers modes for both command-line operations and text editing.Open a file with Vim: vim filenameExit Vim editor: Press Esc, then type :wq and press EnterEmacsEmacs is a versatile text editor with extensive customization capabilities and support for various programming languages.Open a file with Emacs: emacs filenameSave and exit Emacs: Press Ctrl + X, then Ctrl + S and Ctrl + X, then Ctrl + C to exitNanoNano is a simple and user-friendly text editor designed for ease of use and accessibility.Open a file with Nano: nano filenameSave and exit Nano: Press Ctrl + O, then Ctrl + XEdEd is a standard Unix text editor that operates in line-oriented mode, making it suitable for batch processing and automation tasks.Open a file with Ed: ed filenameExit Ed editor: Type q and press EnterJedJed is a lightweight yet powerful text editor that provides an intuitive interface and support for various programming languages.Open a file with Jed: jed filenameSave and exit Jed: Press Alt + X, then type exit and press EnterConclusionIn conclusion, Unix commands serve as a fundamental toolkit for navigating and managing the Unix operating system, which has evolved from its inception in the 1960s to become one of the most widely used OS platforms across various domains including personal computing, servers, and mobile devices. From its origins at Bell Labs with developers Dennis M. Ritchie and Ken Thompson to the birth of the C programming language and the subsequent emergence of Unix-like systems such as Linux, the Unix ecosystem has significantly shaped the computing landscape. Understanding basic Unix commands is essential for users to efficiently manipulate files, manage processes, configure networks, and perform system administration tasks, thereby empowering them to leverage the full potential of Unix-based systems for diverse computing needs. Comment More infoAdvertise with us Next Article How to Find a File in Linux | Find Command H Harsh Wardhan Chaudhary Improve Article Tags : Misc Linux-Unix linux-command Practice Tags : Misc Similar Reads Linux/Unix Tutorial Linux is one of the most widely used open-source operating systems. It's fast, secure, stable, and powers everything from smartphones and servers to cloud platforms and IoT devices. 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