aapropos Search Help manual pages (man -k)apt-get Search for and install software packages (Debian)aptitude Search for and install software packages (Debian)aspell Spell Checkerawk Find and Replace text, database sort/validate/index
bbasename Strip directory and suffix from filenamesbash GNU Bourne-Again SHellbc Arbitrary precision calculator languagebg Send to backgroundbreak Exit from a loopbuiltin Run a shell builtinbzip2 Compress or decompress named file(s)
ccal Display a calendarcase Conditionally perform a commandcat Concatenate and print (display) the content of filescd Change Directorycfdisk Partition table manipulator for Linuxchgrp Change group ownershipchmod Change access permissionschown Change file owner and groupchroot Run a command with a different root directorychkconfig System services (runlevel)cksum Print CRC checksum and byte countsclear Clear terminal screencmp Compare two filescomm Compare two sorted files line by linecommand Run a command – ignoring shell functionscontinue Resume the next iteration of a loopcp Copy one or more files to another locationcron Daemon to execute scheduled commandscrontab Schedule a command to run at a later timecsplit Split a file into context-determined piecescut Divide a file into several parts
ddate Display or change the date & timedc Desk Calculatordd Convert and copy a file, write disk headers, boot recordsddrescue Data recovery tooldeclare Declare variables and give them attributesdf Display free disk spacediff Display the differences between two filesdiff3 Show differences among three filesdig DNS lookupdir Briefly list directory contentsdircolors Colour setup for `ls’dirname Convert a full pathname to just a pathdirs Display list of remembered directoriesdmesg Print kernel & driver messagesdu Estimate file space usage
eecho Display message on screenegrep Search file(s) for lines that match an extended expressioneject Eject removable mediaenable Enable and disable builtin shell commandsenv Environment variablesethtool Ethernet card settingseval Evaluate several commands/argumentsexec Execute a commandexit Exit the shellexpect Automate arbitrary applications accessed over a terminalexpand Convert tabs to spacesexport Set an environment variableexpr Evaluate expressions
ffalse Do nothing, unsuccessfullyfdformat Low-level format a floppy diskfdisk Partition table manipulator for Linuxfg Send job to foregroundfgrep Search file(s) for lines that match a fixed stringfile Determine file typefind Search for files that meet a desired criteriafmt Reformat paragraph textfold Wrap text to fit a specified width.for Expand words, and execute commandsformat Format disks or tapesfree Display memory usagefsck File system consistency check and repairftp File Transfer Protocolfunction Define Function Macrosfuser Identify/kill the process that is accessing a file
ggawk Find and Replace text within file(s)getopts Parse positional parametersgrep Search file(s) for lines that match a given patterngroupadd Add a user security groupgroupdel Delete a groupgroupmod Modify a groupgroups Print group names a user is ingzip Compress or decompress named file(s)
hhash Remember the full pathname of a name argumenthead Output the first part of file(s)help Display help for a built-in commandhistory Command Historyhostname Print or set system name
iiconv Convert the character set of a fileid Print user and group id’sif Conditionally perform a commandifconfig Configure a network interfaceifdown Stop a network interfaceifup Start a network interface upimport Capture an X server screen and save the image to fileinstall Copy files and set attributes
jjobs List active jobsjoin Join lines on a common field
kkill Stop a process from runningkillall Kill processes by name
lless Display output one screen at a timelet Perform arithmetic on shell variablesln Create a symbolic link to a filelocal Create variableslocate Find fileslogname Print current login namelogout Exit a login shelllook Display lines beginning with a given stringlpc Line printer control programlpr Off line printlprint Print a filelprintd Abort a print joblprintq List the print queuelprm Remove jobs from the print queuels List information about file(s)lsof List open files
mmake Recompile a group of programsman Help manualmkdir Create new folder(s)mkfifo Make FIFOs (named pipes)mkisofs Create an hybrid ISO9660/JOLIET/HFS filesystemmknod Make block or character special filesmore Display output one screen at a timemount Mount a file systemmtools Manipulate MS-DOS filesmtr Network diagnostics (traceroute/ping)mv Move or rename files or directoriesmmv Mass Move and rename (files)
nnetstat Networking informationnice Set the priority of a command or jobnl Number lines and write filesnohup Run a command immune to hangupsnotify-send Send desktop notificationsnslookup Query Internet name servers interactively
oopen Open a file in its default applicationop Operator access
ppasswd Modify a user passwordpaste Merge lines of filespathchk Check file name portabilityping Test a network connectionpkill Stop processes from runningpopd Restore the previous value of the current directorypr Prepare files for printingprintcap Printer capability databaseprintenv Print environment variablesprintf Format and print dataps Process statuspushd Save and then change the current directorypwd Print Working Directory
qquota Display disk usage and limitsquotacheck Scan a file system for disk usagequotactl Set disk quotas
rram ram disk devicercp Copy files between two machinesread Read a line from standard inputreadarray Read from stdin into an array variablereadonly Mark variables/functions as readonlyreboot Reboot the systemrename Rename filesrenice Alter priority of running processesremsync Synchronize remote files via emailreturn Exit a shell functionrev Reverse lines of a filerm Remove filesrmdir Remove folder(s)rsync Remote file copy (Synchronize file trees)
sscreen Multiplex terminal, run remote shells via sshscp Secure copy (remote file copy)sdiff Merge two files interactivelysed Stream Editorselect Accept keyboard inputseq Print numeric sequencesset Manipulate shell variables and functionssftp Secure File Transfer Programshift Shift positional parametersshopt Shell Optionsshutdown Shutdown or restart linuxsleep Delay for a specified timeslocate Find filessort Sort text filessource Run commands from a file `.’split Split a file into fixed-size piecesssh Secure Shell client (remote login program)strace Trace system calls and signalssu Substitute user identitysudo Execute a command as another usersum Print a checksum for a filesuspend Suspend execution of this shellsymlink Make a new name for a filesync Synchronize data on disk with memory
ttail Output the last part of filetar Tape ARchivertee Redirect output to multiple filestest Evaluate a conditional expressiontime Measure Program running timetimes User and system timestouch Change file timestampstop List processes running on the systemtraceroute Trace Route to Hosttrap Run a command when a signal is set(bourne)tr Translate, squeeze, and/or delete characterstrue Do nothing, successfullytsort Topological sorttty Print filename of terminal on stdintype Describe a command
uulimit Limit user resourcesumask Users file creation maskumount Unmount a deviceunalias Remove an aliasuname Print system informationunexpand Convert spaces to tabsuniq Uniquify filesunits Convert units from one scale to anotherunset Remove variable or function namesunshar Unpack shell archive scriptsuntil Execute commands (until error)uptime Show uptimeuseradd Create new user accountuserdel Delete a user accountusermod Modify user accountusers List users currently logged inuuencode Encode a binary fileuudecode Decode a file created by uuencode
vv Verbosely list directory contents (`ls -l -b’)vdir Verbosely list directory contents (`ls -l -b’)vi Text Editorvmstat Report virtual memory statistics
wwait Wait for a process to completewatch Execute/display a program periodicallywc Print byte, word, and line countswhereis Search the user’s $path, man pages and source files for a programwhich Search the user’s $path for a program filewhile Execute commandswho Print all usernames currently logged inwhoami Print the current user id and name (`id -un’)wget Retrieve web pages or files via HTTP, HTTPS or FTPwrite Send a message to another user
xxargs Execute utility, passing constructed argument list(s)xdg-open Open a file or URL in the user’s preferred application.
yyes Print a string until interrupted
