# Linux command line: bash + utilities

<table class="az" id="bkmrk-a-%26-start-a-new-proc"><tbody><tr><td>A</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[&amp;](https://ss64.com/bash/bg.html)</td><td>Start a new process in the background</td></tr><tr><td>  
</td><td>[alias](https://ss64.com/bash/alias.html)</td><td>Create an alias •</td></tr><tr><td>  
</td><td>[apropos](https://ss64.com/bash/apropos.html)</td><td>Search Help manual pages (man -k)</td></tr><tr><td>  
</td><td>[apt](https://ss64.com/bash/apt.html)</td><td>Search for and install software packages (Debian/Ubuntu)</td></tr><tr><td>  
</td><td>[apt-get](https://ss64.com/bash/apt-get.html)</td><td>Search for and install software packages (Debian/Ubuntu)</td></tr><tr><td>  
</td><td>[aptitude](https://ss64.com/bash/aptitude.html)</td><td>Search for and install software packages (Debian/Ubuntu)</td></tr><tr><td>  
</td><td>[aspell](https://ss64.com/bash/aspell.html)</td><td>Spell Checker</td></tr><tr><td>  
</td><td>[at](https://ss64.com/bash/at.html)</td><td>Schedule a command to run once at a particular time</td></tr><tr><td>  
</td><td>[awk](https://ss64.com/bash/awk.html)</td><td>Find and Replace text, database sort/validate/index</td></tr><tr><td><a id="bkmrk--0"></a>B</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[basename](https://ss64.com/bash/basename.html)</td><td>Strip directory and suffix from filenames</td></tr><tr><td>  
</td><td>[base32](https://ss64.com/bash/base32.html)</td><td>Base32 encode/decode data and print to standard output</td></tr><tr><td>  
</td><td>[base64](https://ss64.com/bash/base64.html)</td><td>Base64 encode/decode data and print to standard output</td></tr><tr><td>  
</td><td>[bash](https://ss64.com/bash/bash.html)</td><td>GNU Bourne-Again SHell</td></tr><tr><td>  
</td><td>[bc](https://ss64.com/bash/bc.html)</td><td>Arbitrary precision calculator language</td></tr><tr><td>  
</td><td>[bg](https://ss64.com/bash/bg.html)</td><td>Send to background</td></tr><tr><td>  
</td><td>[bind](https://ss64.com/bash/bind.html)</td><td>Set or display readline key and function bindings •</td></tr><tr><td>  
</td><td>[break](https://ss64.com/bash/break.html)</td><td>Exit from a loop •</td></tr><tr><td>  
</td><td>[builtin](https://ss64.com/bash/builtin.html)</td><td>Run a shell builtin</td></tr><tr><td>  
</td><td>[bzip2](https://ss64.com/bash/bzip2.html)</td><td>Compress or decompress named file(s)</td></tr><tr><td><a id="bkmrk--1"></a>C</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[cal](https://ss64.com/bash/cal.html)</td><td>Display a calendar</td></tr><tr><td>  
</td><td>[caller](https://ss64.com/bash/caller.html)</td><td>Return the context of any active subroutine call •</td></tr><tr><td>  
</td><td>[case](https://ss64.com/bash/case.html)</td><td>Conditionally perform a command</td></tr><tr><td>  
</td><td>[cat](https://ss64.com/bash/cat.html)</td><td>Concatenate and print (display) the content of files</td></tr><tr><td>  
</td><td>[cd](https://ss64.com/bash/cd.html)</td><td>Change Directory</td></tr><tr><td>  
</td><td>[cfdisk](https://ss64.com/bash/cfdisk.html)</td><td>Partition table manipulator for Linux</td></tr><tr><td>  
</td><td>[chattr](https://ss64.com/bash/chattr.html)</td><td>Change file attributes on a Linux file system</td></tr><tr><td>  
</td><td>[chgrp](https://ss64.com/bash/chgrp.html)</td><td>Change group ownership</td></tr><tr><td>  
</td><td>[chmod](https://ss64.com/bash/chmod.html)</td><td>Change access permissions</td></tr><tr><td>  
</td><td>[chown](https://ss64.com/bash/chown.html)</td><td>Change file owner and group</td></tr><tr><td>  
</td><td>[chpasswd](https://ss64.com/bash/chpasswd.html)</td><td>Update passwords in batch mode</td></tr><tr><td>  
</td><td>[chroot](https://ss64.com/bash/chroot.html)</td><td>Run a command with a different root directory</td></tr><tr><td>  
</td><td>[chkconfig](https://ss64.com/bash/chkconfig.html)</td><td>System services (runlevel)</td></tr><tr><td>  
</td><td>[cksum](https://ss64.com/bash/cksum.html)</td><td>Print CRC checksum and byte counts</td></tr><tr><td>  
</td><td>clear</td><td>Clear terminal screen</td></tr><tr><td>  
</td><td>[cmp](https://ss64.com/bash/cmp.html)</td><td>Compare two files</td></tr><tr><td>  
</td><td>[comm](https://ss64.com/bash/comm.html)</td><td>Compare two sorted files line by line</td></tr><tr><td>  
</td><td>[command](https://ss64.com/bash/command.html)</td><td>Run a command - ignoring shell functions •</td></tr><tr><td>  
</td><td>[continue](https://ss64.com/bash/continue.html)</td><td>Resume the next iteration of a loop •</td></tr><tr><td>  
</td><td>[cp](https://ss64.com/bash/cp.html)</td><td>Copy one or more files to another location</td></tr><tr><td>  
</td><td>[cpio](https://ss64.com/bash/cpio.html)</td><td>Copy files to and from archives</td></tr><tr><td>  
</td><td>[cron](https://ss64.com/bash/cron.html)</td><td>Daemon to execute scheduled commands</td></tr><tr><td>  
</td><td>[crontab](https://ss64.com/bash/crontab.html)</td><td>Schedule a command to run at a later time</td></tr><tr><td>  
</td><td>[csplit](https://ss64.com/bash/csplit.html)</td><td>Split a file into context-determined pieces</td></tr><tr><td>  
</td><td>[curl](https://ss64.com/bash/curl.html)</td><td>Transfer data from or to a server</td></tr><tr><td>  
</td><td>[cut](https://ss64.com/bash/cut.html)</td><td>Divide a file into several parts</td></tr><tr><td><a id="bkmrk--2"></a>D</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[date](https://ss64.com/bash/date.html)</td><td>Display or change the date &amp; time</td></tr><tr><td>  
</td><td>[dc](https://ss64.com/bash/dc.html)</td><td>Desk Calculator</td></tr><tr><td>  
</td><td>[dd](https://ss64.com/bash/dd.html)</td><td>Data Duplicator - convert and copy a file, write disk headers, boot records</td></tr><tr><td>  
</td><td>[ddrescue](https://ss64.com/bash/ddrescue.html)</td><td>Data recovery tool</td></tr><tr><td>  
</td><td>[declare](https://ss64.com/bash/declare.html)</td><td>Declare variables and give them attributes •</td></tr><tr><td>  
</td><td>[df](https://ss64.com/bash/df.html)</td><td>Display free disk space</td></tr><tr><td>  
</td><td>[diff](https://ss64.com/bash/diff.html)</td><td>Display the differences between two files</td></tr><tr><td>  
</td><td>[diff3](https://ss64.com/bash/diff3.html)</td><td>Show differences among three files</td></tr><tr><td>  
</td><td>[dig](https://ss64.com/bash/dig.html)</td><td>DNS lookup</td></tr><tr><td>  
</td><td>[dir](https://ss64.com/bash/dir.html)</td><td>Briefly list directory contents</td></tr><tr><td>  
</td><td>[dircolors](https://ss64.com/bash/dircolors.html)</td><td>Colour setup for 'ls'</td></tr><tr><td>  
</td><td>[dirname](https://ss64.com/bash/dirname.html)</td><td>Convert a full pathname to just a path</td></tr><tr><td>  
</td><td>[dirs](https://ss64.com/bash/dirs.html)</td><td>Display list of remembered directories</td></tr><tr><td>  
</td><td>[dos2unix](https://ss64.com/bash/dos2unix.html)</td><td>Windows/MAC to UNIX text file format converter</td></tr><tr><td>  
</td><td>[dmesg](https://ss64.com/bash/dmesg.html)</td><td>Print kernel &amp; driver messages</td></tr><tr><td>  
</td><td>[dpkg](https://ss64.com/bash/dpkg.html)</td><td>Package manager (Debian/Ubuntu).</td></tr><tr><td>  
</td><td>[du](https://ss64.com/bash/du.html)</td><td>Estimate file space usage</td></tr><tr><td><a id="bkmrk--3"></a>E</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[echo](https://ss64.com/bash/echo.html)</td><td>Display message on screen •</td></tr><tr><td>  
</td><td>[egrep](https://ss64.com/bash/egrep.html)</td><td>Search file(s) for lines that match an extended expression</td></tr><tr><td>  
</td><td>[eject](https://ss64.com/bash/eject.html)</td><td>Eject removable media</td></tr><tr><td>  
</td><td>[enable](https://ss64.com/bash/enable.html)</td><td>Enable and disable builtin shell commands •</td></tr><tr><td>  
</td><td>[env](https://ss64.com/bash/env.html)</td><td>Environment variables</td></tr><tr><td>  
</td><td>ethtool</td><td>Ethernet card settings</td></tr><tr><td>  
</td><td>[eval](https://ss64.com/bash/eval.html)</td><td>Evaluate several commands/arguments</td></tr><tr><td>  
</td><td>[exec](https://ss64.com/bash/exec.html)</td><td>Execute a command</td></tr><tr><td>  
</td><td>[exit](https://ss64.com/bash/exit.html)</td><td>Exit the shell</td></tr><tr><td>  
</td><td>[expand](https://ss64.com/bash/expand.html)</td><td>Convert tabs to spaces</td></tr><tr><td>  
</td><td>[export](https://ss64.com/bash/export.html)</td><td>Set an environment variable</td></tr><tr><td>  
</td><td>[expr](https://ss64.com/bash/expr.html)</td><td>Evaluate expressions</td></tr><tr><td><a id="bkmrk--4"></a>F</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[false](https://ss64.com/bash/false.html)</td><td>Do nothing, unsuccessfully</td></tr><tr><td>  
</td><td>[fdformat](https://ss64.com/bash/fdformat.html)</td><td>Low-level format a floppy disk</td></tr><tr><td>  
</td><td>[fdisk](https://ss64.com/bash/fdisk.html)</td><td>Partition table manipulator for Linux</td></tr><tr><td>  
</td><td>[fg](https://ss64.com/bash/fg.html)</td><td>Send job to foreground</td></tr><tr><td>  
</td><td>[fgrep](https://ss64.com/bash/fgrep.html)</td><td>Search file(s) for lines that match a fixed string</td></tr><tr><td>  
</td><td>[file](https://ss64.com/bash/file.html)</td><td>Determine file type</td></tr><tr><td>  
</td><td>[find](https://ss64.com/bash/find.html)</td><td>Search for files that meet a desired criteria</td></tr><tr><td>  
</td><td>[fmt](https://ss64.com/bash/fmt.html)</td><td>Reformat paragraph text</td></tr><tr><td>  
</td><td>[fold](https://ss64.com/bash/fold.html)</td><td>Wrap text to fit a specified width</td></tr><tr><td>  
</td><td>[for](https://ss64.com/bash/for.html)</td><td>Expand *words*, and execute *commands*</td></tr><tr><td>  
</td><td>format</td><td>Format disks or tapes</td></tr><tr><td>  
</td><td>free</td><td>Display memory usage</td></tr><tr><td>  
</td><td>[fsck](https://ss64.com/bash/fsck.html)</td><td>File system consistency check and repair</td></tr><tr><td>  
</td><td>[ftp](https://ss64.com/bash/ftp.html)</td><td>File Transfer Protocol</td></tr><tr><td>  
</td><td>[function](https://ss64.com/bash/function.html)</td><td>Define Function Macros</td></tr><tr><td>  
</td><td>[fuser](https://ss64.com/bash/fuser.html)</td><td>Identify/kill the process that is accessing a file</td></tr><tr><td><a id="bkmrk--5"></a>G</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[gawk](https://ss64.com/bash/awk.html)</td><td>Find and Replace text within file(s)</td></tr><tr><td>  
</td><td>[getopts](https://ss64.com/bash/getopts.html)</td><td>Parse positional parameters</td></tr><tr><td>  
</td><td>[getfacl](https://ss64.com/bash/getfacl.html)</td><td>Get file access control lists</td></tr><tr><td>  
</td><td>[grep](https://ss64.com/bash/grep.html)</td><td>Search file(s) for lines that match a given pattern</td></tr><tr><td>  
</td><td>[groupadd](https://ss64.com/bash/groupadd.html)</td><td>Add a user security group</td></tr><tr><td>  
</td><td>[groupdel](https://ss64.com/bash/groupdel.html)</td><td>Delete a group</td></tr><tr><td>  
</td><td>[groupmod](https://ss64.com/bash/groupmod.html)</td><td>Modify a group</td></tr><tr><td>  
</td><td>[groups](https://ss64.com/bash/groups.html)</td><td>Print group names a user is in</td></tr><tr><td>  
</td><td>[gzip](https://ss64.com/bash/gzip.html)</td><td>Compress or decompress named file(s)</td></tr><tr><td><a id="bkmrk--6"></a>H</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[hash](https://ss64.com/bash/hash.html)</td><td>Remember the full pathname of a name argument</td></tr><tr><td>  
</td><td>[head](https://ss64.com/bash/head.html)</td><td>Output the first part of file(s)</td></tr><tr><td>  
</td><td>help</td><td>Display help for a built-in command •</td></tr><tr><td>  
</td><td>[history](https://ss64.com/bash/history.html)</td><td>Command History</td></tr><tr><td>  
</td><td>[hostname](https://ss64.com/bash/hostname.html)</td><td>Print or set system name</td></tr><tr><td>  
</td><td>[htop](https://ss64.com/bash/htop.html)</td><td>Interactive process viewer</td></tr><tr><td><a id="bkmrk--7"></a>I</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[iconv](https://ss64.com/bash/iconv.html)</td><td>Convert the character set of a file</td></tr><tr><td>  
</td><td>[id](https://ss64.com/bash/id.html)</td><td>Print user and group id's</td></tr><tr><td>  
</td><td>[if](https://ss64.com/bash/if.html)</td><td>Conditionally perform a command</td></tr><tr><td>  
</td><td>[ifconfig](https://ss64.com/bash/ifconfig.html)</td><td>Configure a network interface</td></tr><tr><td>  
</td><td>[ifdown](https://ss64.com/bash/ifup.html)</td><td>Stop a network interface</td></tr><tr><td>  
</td><td>[ifup](https://ss64.com/bash/ifup.html)</td><td>Start a network interface up</td></tr><tr><td>  
</td><td>[import](https://ss64.com/bash/import.html)</td><td>Capture an X server screen and save the image to file</td></tr><tr><td>  
</td><td>[install](https://ss64.com/bash/install.html)</td><td>Copy files and set attributes</td></tr><tr><td>  
</td><td>[iostat](https://ss64.com/bash/iostat.html)</td><td>Report CPU and i/o statistics</td></tr><tr><td>  
</td><td>[ip](https://ss64.com/bash/ip.html)</td><td>Routing, devices and tunnels</td></tr><tr><td><a id="bkmrk--8"></a>J</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[jobs](https://ss64.com/bash/jobs.html)</td><td>List active jobs •</td></tr><tr><td>  
</td><td>[join](https://ss64.com/bash/join.html)</td><td>Join lines on a common field</td></tr><tr><td><a id="bkmrk--9"></a>K</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[kill](https://ss64.com/bash/kill.html)</td><td>Kill a process by specifying its PID</td></tr><tr><td>  
</td><td>[killall](https://ss64.com/bash/killall.html)</td><td>Kill processes by name</td></tr><tr><td>  
</td><td>[klist](https://ss64.com/bash/klist.html)</td><td>List cached Kerberos tickets</td></tr><tr><td><a id="bkmrk--10"></a>L</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[less](https://ss64.com/bash/less.html)</td><td>Display output one screen at a time</td></tr><tr><td>  
</td><td>[let](https://ss64.com/bash/let.html)</td><td>Perform arithmetic on shell variables •</td></tr><tr><td>  
</td><td>[link](https://ss64.com/bash/link.html)</td><td>Create a link to a file</td></tr><tr><td>  
</td><td>[ln](https://ss64.com/bash/ln.html)</td><td>Create a symbolic link to a file</td></tr><tr><td>  
</td><td>[local](https://ss64.com/bash/local.html)</td><td>Create a function variable •</td></tr><tr><td>  
</td><td>[locate](https://ss64.com/bash/locate.html)</td><td>Find files</td></tr><tr><td>  
</td><td>[logname](https://ss64.com/bash/logname.html)</td><td>Print current login name</td></tr><tr><td>  
</td><td>[logout](https://ss64.com/bash/logout.html)</td><td>Exit a login shell •</td></tr><tr><td>  
</td><td>[look](https://ss64.com/bash/look.html)</td><td>Display lines beginning with a given string</td></tr><tr><td>  
</td><td>[lpc](https://ss64.com/bash/lpc.html)</td><td>Line printer control program</td></tr><tr><td>  
</td><td>[lpr](https://ss64.com/bash/lpr.html)</td><td>Print files</td></tr><tr><td>  
</td><td>lprint</td><td>Print a file</td></tr><tr><td>  
</td><td>lprintd</td><td>Delete a print job</td></tr><tr><td>  
</td><td>lprintq</td><td>List the print queue</td></tr><tr><td>  
</td><td>[lprm](https://ss64.com/bash/lprm.html)</td><td>Remove jobs from the print queue</td></tr><tr><td>  
</td><td>[lsattr](https://ss64.com/bash/lsattr.html)</td><td>List file attributes on a Linux second extended file system</td></tr><tr><td>  
</td><td>[lsblk](https://ss64.com/bash/lsblk.html)</td><td>List block devices</td></tr><tr><td>  
</td><td>[ls](https://ss64.com/bash/ls.html)</td><td>List information about file(s)</td></tr><tr><td>  
</td><td>[lsof](https://ss64.com/bash/lsof.html)</td><td>List open files</td></tr><tr><td>  
</td><td>[lspci](https://ss64.com/bash/lspci.html)</td><td>List all PCI devices</td></tr><tr><td><a id="bkmrk--11"></a>M</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>make</td><td>Recompile a group of programs</td></tr><tr><td>  
</td><td>[man](https://ss64.com/bash/man.html)</td><td>Help manual</td></tr><tr><td>  
</td><td>[mapfile](https://ss64.com/bash/mapfile.html)</td><td>Read lines from standard input into an indexed array variable •</td></tr><tr><td>  
</td><td>[mkdir](https://ss64.com/bash/mkdir.html)</td><td>Create new folder(s)</td></tr><tr><td>  
</td><td>[mkfifo](https://ss64.com/bash/mkfifo.html)</td><td>Make FIFOs (named pipes)</td></tr><tr><td>  
</td><td>[mkfile](https://ss64.com/bash/mkfile.html)</td><td>Make a file</td></tr><tr><td>  
</td><td>mkisofs</td><td>Create a hybrid ISO9660/JOLIET/HFS filesystem</td></tr><tr><td>  
</td><td>[mknod](https://ss64.com/bash/mknod.html)</td><td>Make block or character special files</td></tr><tr><td>  
</td><td>[mktemp](https://ss64.com/bash/mktemp.html)</td><td>Make a temporary file</td></tr><tr><td>  
</td><td>[more](https://ss64.com/bash/more.html)</td><td>Display output one screen at a time</td></tr><tr><td>  
</td><td>[most](https://ss64.com/bash/most.html)</td><td>Browse or page through a text file</td></tr><tr><td>  
</td><td>[mount](https://ss64.com/bash/mount.html)</td><td>Mount a file system</td></tr><tr><td>  
</td><td>[mtools](https://ss64.com/bash/mtools.html)</td><td>Manipulate MS-DOS files</td></tr><tr><td>  
</td><td>[mtr](https://ss64.com/bash/mtr.html)</td><td>Network diagnostics (traceroute/ping)</td></tr><tr><td>  
</td><td>[mv](https://ss64.com/bash/mv.html)</td><td>Move or rename files or directories</td></tr><tr><td>  
</td><td>[mmv](https://ss64.com/bash/mmv.html)</td><td>Mass Move and rename (files)</td></tr><tr><td><a id="bkmrk--12"></a>N</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[nc](https://ss64.com/bash/nc.html)</td><td>Netcat, read and write data across networks</td></tr><tr><td>  
</td><td>[netstat](https://ss64.com/bash/netstat.html)</td><td>Networking connections/stats</td></tr><tr><td>  
</td><td>[nft](https://ss64.com/bash/nft.html)</td><td>nftables for packet filtering and classification</td></tr><tr><td>  
</td><td>[nice](https://ss64.com/bash/nice.html)</td><td>Set the priority of a command or job</td></tr><tr><td>  
</td><td>[nl](https://ss64.com/bash/nl.html)</td><td>Number lines and write files</td></tr><tr><td>  
</td><td>[nohup](https://ss64.com/bash/nohup.html)</td><td>Run a command immune to hangups</td></tr><tr><td>  
</td><td>[notify-send](https://ss64.com/bash/notify-send.html)</td><td>Send desktop notifications</td></tr><tr><td>  
</td><td>[nslookup](https://ss64.com/bash/nslookup.html)</td><td>Query Internet name servers interactively</td></tr><tr><td><a id="bkmrk--13"></a>O</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[open](https://ss64.com/bash/open.html)</td><td>Open a file in its default application</td></tr><tr><td>  
</td><td>[op](https://ss64.com/bash/op.html)</td><td>Operator access</td></tr><tr><td><a id="bkmrk--14"></a>P</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[passwd](https://ss64.com/bash/passwd.html)</td><td>Modify a user password</td></tr><tr><td>  
</td><td>[paste](https://ss64.com/bash/paste.html)</td><td>Merge lines of files</td></tr><tr><td>  
</td><td>pathchk</td><td>Check file name portability</td></tr><tr><td>  
</td><td>[Perf](https://ss64.com/bash/perf.html)</td><td>Performance analysis tools for Linux</td></tr><tr><td>  
</td><td>[ping](https://ss64.com/bash/ping.html)</td><td>Test a network connection</td></tr><tr><td>  
</td><td>[pgrep](https://ss64.com/bash/pkill.html)</td><td>List processes by name</td></tr><tr><td>  
</td><td>[pkill](https://ss64.com/bash/pkill.html)</td><td>Kill processes by name</td></tr><tr><td>  
</td><td>[popd](https://ss64.com/bash/popd.html)</td><td>Restore the previous value of the current directory</td></tr><tr><td>  
</td><td>[pr](https://ss64.com/bash/pr.html)</td><td>Prepare files for printing</td></tr><tr><td>  
</td><td>printcap</td><td>Printer capability database</td></tr><tr><td>  
</td><td>[printenv](https://ss64.com/bash/printenv.html)</td><td>Print environment variables</td></tr><tr><td>  
</td><td>[printf](https://ss64.com/bash/printf.html)</td><td>Format and print data •</td></tr><tr><td>  
</td><td>[ps](https://ss64.com/bash/ps.html)</td><td>Process status</td></tr><tr><td>  
</td><td>[pushd](https://ss64.com/bash/pushd.html)</td><td>Save and then change the current directory</td></tr><tr><td>  
</td><td>[pv](https://ss64.com/bash/pv.html)</td><td>Monitor the progress of data through a pipe</td></tr><tr><td>  
</td><td>[pwd](https://ss64.com/bash/pwd.html)</td><td>Print Working Directory</td></tr><tr><td><a id="bkmrk--15"></a>Q</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[quota](https://ss64.com/bash/quota.html)</td><td>Display disk usage and limits</td></tr><tr><td>  
</td><td>[quotacheck](https://ss64.com/bash/quotacheck.html)</td><td>Scan a file system for disk usage</td></tr><tr><td><a id="bkmrk--16"></a>R</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[ram](https://ss64.com/bash/ram.html)</td><td>ram disk device</td></tr><tr><td>  
</td><td>[rar](https://ss64.com/bash/rar.html)</td><td>Archive files with compression</td></tr><tr><td>  
</td><td>[rcp](https://ss64.com/bash/rcp.html)</td><td>Copy files between two machines</td></tr><tr><td>  
</td><td>[read](https://ss64.com/bash/read.html)</td><td>Read a line from standard input •</td></tr><tr><td>  
</td><td>[readarray](https://ss64.com/bash/mapfile.html)</td><td>Read from stdin into an array variable •</td></tr><tr><td>  
</td><td>[readonly](https://ss64.com/bash/readonly.html)</td><td>Mark variables/functions as readonly</td></tr><tr><td>  
</td><td>reboot</td><td>Reboot the system</td></tr><tr><td>  
</td><td>[rename](https://ss64.com/bash/rename.html)</td><td>Rename files</td></tr><tr><td>  
</td><td>renice</td><td>Alter priority of running processes</td></tr><tr><td>  
</td><td>remsync</td><td>Synchronize remote files via email</td></tr><tr><td>  
</td><td>[return](https://ss64.com/bash/return.html)</td><td>Exit a shell function</td></tr><tr><td>  
</td><td>[rev](https://ss64.com/bash/rev.html)</td><td>Reverse lines of a file</td></tr><tr><td>  
</td><td>[rm](https://ss64.com/bash/rm.html)</td><td>Remove files</td></tr><tr><td>  
</td><td>[rmdir](https://ss64.com/bash/rmdir.html)</td><td>Remove folder(s)</td></tr><tr><td>  
</td><td>[rsync](https://ss64.com/bash/rsync.html)</td><td>Remote file copy (Synchronize file trees)</td></tr><tr><td><a id="bkmrk--17"></a>S</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[screen](https://ss64.com/bash/screen.html)</td><td>Multiplex terminal, run remote shells via ssh</td></tr><tr><td>  
</td><td>[scp](https://ss64.com/bash/scp.html)</td><td>Secure copy (remote file copy)</td></tr><tr><td>  
</td><td>[sdiff](https://ss64.com/bash/sdiff.html)</td><td>Merge two files interactively</td></tr><tr><td>  
</td><td>[sed](https://ss64.com/bash/sed.html)</td><td>Stream Editor</td></tr><tr><td>  
</td><td>[select](https://ss64.com/bash/select.html)</td><td>Accept user choices via keyboard input</td></tr><tr><td>  
</td><td>[seq](https://ss64.com/bash/seq.html)</td><td>Print numeric sequences</td></tr><tr><td>  
</td><td>[set](https://ss64.com/bash/set.html)</td><td>Manipulate shell variables and functions</td></tr><tr><td>  
</td><td>[setfacl](https://ss64.com/bash/setfacl.html)</td><td>Set file access control lists.</td></tr><tr><td>  
</td><td>sftp</td><td>Secure File Transfer Program</td></tr><tr><td>  
</td><td>[sha256sum](https://ss64.com/bash/sha256sum.html)</td><td>Compute and check SHA256 (256-bit) checksums</td></tr><tr><td>  
</td><td>[shift](https://ss64.com/bash/shift.html)</td><td>Shift positional parameters</td></tr><tr><td>  
</td><td>[shopt](https://ss64.com/bash/shopt.html)</td><td>Shell Options</td></tr><tr><td>  
</td><td>[shuf](https://ss64.com/bash/shuf.html)</td><td>Generate random permutations</td></tr><tr><td>  
</td><td>[shutdown](https://ss64.com/bash/shutdown.html)</td><td>Shutdown or restart linux</td></tr><tr><td>  
</td><td>[sleep](https://ss64.com/bash/sleep.html)</td><td>Delay for a specified time</td></tr><tr><td>  
</td><td>[slocate](https://ss64.com/bash/slocate.html)</td><td>Find files</td></tr><tr><td>  
</td><td>[sort](https://ss64.com/bash/sort.html)</td><td>Sort text files</td></tr><tr><td>  
</td><td>[source](https://ss64.com/bash/source.html)</td><td>Run commands from a file '.' •</td></tr><tr><td>  
</td><td>[split](https://ss64.com/bash/split.html)</td><td>Split a file into fixed-size pieces</td></tr><tr><td>  
</td><td>[ss](https://ss64.com/bash/ss.html)</td><td>Socket Statistics</td></tr><tr><td>  
</td><td>[ssh](https://ss64.com/bash/ssh.html)</td><td>Secure Shell client (remote login program)</td></tr><tr><td>  
</td><td>[stat](https://ss64.com/bash/stat.html)</td><td>Display file or file system status</td></tr><tr><td>  
</td><td>[strace](https://ss64.com/bash/strace.html)</td><td>Trace system calls and signals</td></tr><tr><td>  
</td><td>[su](https://ss64.com/bash/su.html)</td><td>Substitute user identity</td></tr><tr><td>  
</td><td>[sudo](https://ss64.com/bash/sudo.html)</td><td>Execute a command as another user</td></tr><tr><td>  
</td><td>[sum](https://ss64.com/bash/sum.html)</td><td>Print a checksum for a file</td></tr><tr><td>  
</td><td>[suspend](https://ss64.com/bash/suspend.html)</td><td>Suspend execution of this shell •</td></tr><tr><td>  
</td><td>[sync](https://ss64.com/bash/sync.html)</td><td>Synchronize data on disk with memory</td></tr><tr><td><a id="bkmrk--18"></a>T</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[tail](https://ss64.com/bash/tail.html)</td><td>Output the last part of a file</td></tr><tr><td>  
</td><td>[tar](https://ss64.com/bash/tar.html)</td><td>Store, list or extract files in an archive</td></tr><tr><td>  
</td><td>[tee](https://ss64.com/bash/tee.html)</td><td>Redirect output to multiple files</td></tr><tr><td>  
</td><td>[test](https://ss64.com/bash/test.html)</td><td>Evaluate a conditional expression</td></tr><tr><td>  
</td><td>[time](https://ss64.com/bash/time.html)</td><td>Measure Program running time</td></tr><tr><td>  
</td><td>[timeout](https://ss64.com/bash/timeout.html)</td><td>Run a command with a time limit</td></tr><tr><td>  
</td><td>[times](https://ss64.com/bash/times.html)</td><td>User and system times</td></tr><tr><td>  
</td><td>[tmux](https://ss64.com/bash/tmux.html)</td><td>Terminal multiplexer</td></tr><tr><td>  
</td><td>[touch](https://ss64.com/bash/touch.html)</td><td>Change file timestamps</td></tr><tr><td>  
</td><td>[top](https://ss64.com/bash/top.html)</td><td>List processes running on the system</td></tr><tr><td>  
</td><td>[tput](https://ss64.com/bash/tput.html)</td><td>Set terminal-dependent capabilities, color, position</td></tr><tr><td>  
</td><td>[traceroute](https://ss64.com/bash/traceroute.html)</td><td>Trace Route to Host</td></tr><tr><td>  
</td><td>[trap](https://ss64.com/bash/trap.html)</td><td>Execute a command when the shell receives a signal •</td></tr><tr><td>  
</td><td>[tr](https://ss64.com/bash/tr.html)</td><td>Translate, squeeze, and/or delete characters</td></tr><tr><td>  
</td><td>[true](https://ss64.com/bash/true.html)</td><td>Do nothing, successfully</td></tr><tr><td>  
</td><td>[tsort](https://ss64.com/bash/tsort.html)</td><td>Topological sort</td></tr><tr><td>  
</td><td>[tty](https://ss64.com/bash/tty.html)</td><td>Print filename of terminal on stdin</td></tr><tr><td>  
</td><td>[type](https://ss64.com/bash/type.html)</td><td>Describe a command •</td></tr><tr><td><a id="bkmrk--19"></a>U</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[ulimit](https://ss64.com/bash/ulimit.html)</td><td>Limit user resources •</td></tr><tr><td>  
</td><td>[umask](https://ss64.com/bash/umask.html)</td><td>Users file creation mask</td></tr><tr><td>  
</td><td>umount</td><td>Unmount a device</td></tr><tr><td>  
</td><td>[unalias](https://ss64.com/bash/alias.html)</td><td>Remove an alias •</td></tr><tr><td>  
</td><td>[uname](https://ss64.com/bash/uname.html)</td><td>Print system information</td></tr><tr><td>  
</td><td>[unexpand](https://ss64.com/bash/unexpand.html)</td><td>Convert spaces to tabs</td></tr><tr><td>  
</td><td>[uniq](https://ss64.com/bash/uniq.html)</td><td>Uniquify files</td></tr><tr><td>  
</td><td>[units](https://ss64.com/bash/units.html)</td><td>Convert units from one scale to another</td></tr><tr><td>  
</td><td>[unix2dos](https://ss64.com/bash/unix2dos.html)</td><td>UNIX to Windows or MAC text file format converter</td></tr><tr><td>  
</td><td>[unrar](https://ss64.com/bash/unrar.html)</td><td>Extract files from a rar archive</td></tr><tr><td>  
</td><td>[unset](https://ss64.com/bash/unset.html)</td><td>Remove variable or function names</td></tr><tr><td>  
</td><td>[unshar](https://ss64.com/bash/unshar.html)</td><td>Unpack shell archive scripts</td></tr><tr><td>  
</td><td>[until](https://ss64.com/bash/until.html)</td><td>Execute commands (until error)</td></tr><tr><td>  
</td><td>uptime</td><td>Show uptime</td></tr><tr><td>  
</td><td>[useradd](https://ss64.com/bash/useradd.html)</td><td>Create new user account</td></tr><tr><td>  
</td><td>[userdel](https://ss64.com/bash/userdel.html)</td><td>Delete a user account</td></tr><tr><td>  
</td><td>[usermod](https://ss64.com/bash/usermod.html)</td><td>Modify user account</td></tr><tr><td>  
</td><td>[users](https://ss64.com/bash/users.html)</td><td>List users currently logged in</td></tr><tr><td>  
</td><td>[uuencode](https://ss64.com/bash/uuencode.html)</td><td>Encode a binary file</td></tr><tr><td>  
</td><td>[uudecode](https://ss64.com/bash/uuencode.html)</td><td>Decode a file created by uuencode</td></tr><tr><td><a id="bkmrk--20"></a>V</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>v</td><td>Verbosely list directory contents ('ls -l -b')</td></tr><tr><td>  
</td><td>vdir</td><td>Verbosely list directory contents ('ls -l -b')</td></tr><tr><td>  
</td><td>[vi](https://ss64.com/vi.html)</td><td>Text Editor</td></tr><tr><td>  
</td><td>[vmstat](https://ss64.com/bash/vmstat.html)</td><td>Report virtual memory statistics</td></tr><tr><td><a id="bkmrk--21"></a>W</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[w](https://ss64.com/bash/w.html)</td><td>Show who is logged on and what they are doing</td></tr><tr><td>  
</td><td>[wait](https://ss64.com/bash/wait.html)</td><td>Wait for a process to complete •</td></tr><tr><td>  
</td><td>[watch](https://ss64.com/bash/watch.html)</td><td>Execute/display a program periodically</td></tr><tr><td>  
</td><td>[wc](https://ss64.com/bash/wc.html)</td><td>Print byte, word, and line counts</td></tr><tr><td>  
</td><td>[whereis](https://ss64.com/bash/whereis.html)</td><td>Search the user's $path, man pages and source files for a program</td></tr><tr><td>  
</td><td>[which](https://ss64.com/bash/which.html)</td><td>Search the user's $path for a program file</td></tr><tr><td>  
</td><td>[while](https://ss64.com/bash/while.html)</td><td>Execute commands</td></tr><tr><td>  
</td><td>[who](https://ss64.com/bash/who.html)</td><td>Print all usernames currently logged in</td></tr><tr><td>  
</td><td>[whoami](https://ss64.com/bash/whoami.html)</td><td>Print the current user id and name ('id -un')</td></tr><tr><td>  
</td><td>wget</td><td>Retrieve web pages or files via HTTP, HTTPS or FTP</td></tr><tr><td>  
</td><td>[write](https://ss64.com/bash/write.html)</td><td>Send a message to another user</td></tr><tr><td>X</td><td>  
</td><td>  
</td></tr><tr><td>  
</td><td>[xargs](https://ss64.com/bash/xargs.html)</td><td>Execute utility, passing constructed argument list(s)</td></tr><tr><td>  
</td><td>[xdg-open](https://ss64.com/bash/xdg-open.html)</td><td>Open a file or URL in the user's preferred application.</td></tr><tr><td>  
</td><td>[xxd](https://ss64.com/bash/xxd.html)</td><td>Make a hexdump or do the reverse</td></tr><tr><td>  
</td><td>[xz](https://ss64.com/bash/xz.html)</td><td>Compress or decompress .xz and .lzma files</td></tr><tr><td>  
</td><td>[yes](https://ss64.com/bash/yes.html)</td><td>Print a string until interrupted</td></tr><tr><td>  
</td><td>[zip](https://ss64.com/bash/zip.html)</td><td>Package and compress (archive) files</td></tr><tr><td>  
</td><td>[.](https://ss64.com/bash/source.html)</td><td>[Run](https://ss64.com/bash/source.html) a command script in the current shell</td></tr><tr><td>  
</td><td>[!!](https://ss64.com/bash/bang.html)</td><td>Run the [last](https://ss64.com/bash/bang.html) command again</td></tr><tr><td>  
</td><td>[\###](https://ss64.com/bash/rem.html)</td><td>Comment / [Rem](https://ss64.com/bash/rem.html)ark</td></tr></tbody></table>

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