Glossary
This section contains an alphabetical overview of common UNIX commands. More information about the usage can be found in the man or info pages.
A a2ps
Format files for printing on a PostScript printer.
acroread adduser
PDF viewer.
Create a new user or update default new user information.
alias anacron
Create a shell alias for a command.
Execute commands periodically, does not assume continuously running machine.
apropos
Search the whatis database for strings.
apt-get
APT package handling utility.
aspell
Spell checker.
at, atq, atrm
Queue, examine or delete jobs for later execution.
aumix
Adjust audio mixer.
(g)awk
Pattern scanning and processing language.
B bash
Bourne Again SHell.
batch
Queue, examine or delete jobs for later execution.
bg bitmap
Run a job in the background.
Bitmap editor and converter utilities for the X window System.
bzip2
A block-sorting file compressor.
C cat
Concatenate files and print to standard output.
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cd
Change directory.
cdp/cdplay
An interactive text-mode program for controlling and playing audio CD Roms under Linux.
cdparanoia
An audio CD reading utility which includes extra data verification features.
cdrecord
Record a CD-R.
chattr
Change file attributes.
chgrp
Change group ownership.
chkconfig
Update or query run level information for system services.
chmod
Change file access permissions.
chown
Change file owner and group.
compress
Compress files.
cp crontab
Copy files and directories.
Maintain crontab files.
csh
Open a C shell.
cut
Remove sections from each line of file(s).
D date
Print or set system date and time.
dd
Convert and copy a file (disk dump).
df
Report file system disk usage.
dhcpcd
DHCP client daemon.
diff
Find differences between two files.
dig
Send domain name query packets to name servers.
dmesg
Print or control the kernel ring buffer.
du
Estimate file space usage.
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E echo
Display a line of text.
ediff
Diff to English translator.
egrep
Extended grep.
eject
Unmount and eject removable media.
emacs
Start the Emacs editor.
exec
Invoke subprocess(es).
exit export
Exit current shell.
Add function(s) to the shell environment.
F fax2ps
Convert a TIFF facsimile to PostScript.
fdformat
Format floppy disk.
fdisk
Partition table manipulator for Linux.
fetchmail
Fetch mail from a POP, IMAP, ETRN or ODMR-capable server.
fg
Bring a job in the foreground.
file
Determine file type.
find
Find files.
formail
Mail (re)formatter.
fortune
Print a random, hopefully interesting adage.
ftp
Transfer files (unsafe unless anonymous account is used!)services.
G galeon
Graphical web browser.
gdm
Gnome Display Manager.
(min/a)getty
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gimp
Control console devices.
Image manipulation program.
grep
Print lines matching a pattern.
grub
The grub shell.
gv
A PostScript and PDF viewer.
gzip
Compress or expand files.
H halt
Stop the system.
head
Output the first part of files.
help
Display help on a shell built-in command.
host
DNS lookup utility.
httpd
Apache hypertext transfer protocol server.
I id
Print real and effective UIDs and GIDs.
ifconfig
Configure network interface or show configuration.
info
Read Info documents.
init
Process control initialization.
iostat
Display I/O statistics.
ip ipchains
Display/change network interface status.
IP firewall administration.
iptables
IP packet filter administration.
J jar jobs
Java archive tool.
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List backgrounded tasks.
K kdm kill(all)
Desktop manager for KDE.
Terminate process(es).
ksh
Open a Korn shell.
L ldapmodify
Modify an LDAP entry.
ldapsearch
LDAP search tool.
less more
with features.
lilo
Linux boot loader.
links
Text mode WWW browser.
ln
Make links between files.
loadkeys
Load keyboard translation tables.
locate
Find files.
logout
Close current shell.
lp
Send requests to the LP print service.
lpc
Line printer control program.
lpq
Print spool queue examination program.
lpr
Offline print.
lprm
Remove print requests.
ls
List directory content.
lynx
Text mode WWW browser.
M mail
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Send and receive mail.
man
Read man pages.
mcopy
Copy MSDOS files to/from Unix.
mdir
Display an MSDOS directory.
memusage
Display memory usage.
memusagestat
Display memory usage statistics.
mesg
Control write access to your terminal.
mformat
Add an MSDOS file system to a low-level formatted floppy disk.
mkbootdisk
Creates a stand-alone boot floppy for the running system.
mkdir
Create directory.
mkisofs
Create a hybrid ISO9660 filesystem.
more
Filter for displaying text one screen at the time.
mount
Mount a file system or display information about mounted file systems.
mozilla
Web browser.
mt
Control magnetic tape drive operation.
mtr
Network diagnostic tool.
mv
Rename files.
N named
Internet domain name server.
ncftp
Browser program for ftp services (insecure!).
netstat
Print network connections, routing tables, interface statistics, masquerade connections, and multi-cast memberships.
nfsstat
Print statistics about networked file systems.
nice
Run a program with modified scheduling priority.
nmap
Network exploration tool and security scanner.
ntsysv
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Simple interface for configuring run levels.
P passwd
Change password.
pdf2ps
Ghostscript PDF to PostScript translator.
perl
Practical Extraction and Report Language.
pg
Page through text output.
ping
Send echo request to a host.
pr
Convert text files for printing.
printenv
Print all or part of environment.
procmail
Autonomous mail processor.
ps
Report process status.
pstree
Display a tree of processes.
pwd
Print present working directory.
Q quota
Display disk usage and limits.
R rcp
Remote copy (unsafe!)
rdesktop
Remote Desktop Protocol client.
reboot
Stop and restart the system.
renice
Alter priority of a running process.
rlogin
Remote login (telnet, insecure!).
rm
Remove a file.
rmdir
Remove a directory.
rpm
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rsh
RPM Package Manager.
Remote shell (insecure!).
S scp
Secure remote copy.
screen
Screen manager with VT100 emulation.
set
Display, set or change variable.
setterm
Set terminal attributes.
sftp
Secure (encrypted) ftp.
sh
Open a standard shell.
shutdown
Bring the system down.
sleep
Wait for a given period.
slocate
Security Enhanced version of the GNU Locate.
slrnn
text mode Usenet client.
snort
Network intrusion detection tool.
sort
Sort lines of text files.
ssh
Secure shell.
ssh-keygen
Authentication key generation.
stty
Change and print terminal line settings.
su
Switch user.
T tac
Concatenate and print files in reverse.
tail
Output the last part of files.
talk
Talk to a user.
tar
Archiving utility.
tcsh
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Open a Turbo C shell.
telnet
User interface to the TELNET protocol (insecure!).
tex
Text formatting and typesetting.
time
Time a simple command or give resource usage.
tin
News reading program.
top
Display top CPU processes.
touch
Change file timestamps.
traceroute
Print the route packets take to network host.
tripwire
A file integrity checker for UNIX systems.
twm
Tab Window Manager for the X Window System.
U ulimit
Controll resources.
umask umount
Set user file creation mask.
Unmount a file system.
uncompress
Decompress compressed files.
uniq
Remove duplicate lines from a sorted file.
update
Kernel daemon to flush dirty buffers back to disk.
uptime
Display system uptime and average load.
userdel
Delete a user account and related files.
V vi(m)
Start the vi (improved) editor.
vimtutor
The Vim tutor.
vmstat
Report virtual memory statistics.
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W w
Show who is logged on and what they are doing.
wall
Send a message to everybody's terminal.
wc
Print the number of bytes, words and lines in files.
which
Shows the full path of (shell) commands.
who
Show who is logged on.
who am i
Print effective user ID.
whois
Query a whois or nicname database.
write
Send a message to another user.
X xauth
X authority file utility.
xcdroast
Graphical front end to cdrecord.
xclock
Analog/digital clock for X.
xconsole
Monitor system console messages with X.
xdm
X Display Manager with support for XDMCP, host chooser.
xdvi
DVI viewer.
xfs
X font server.
xhost
Server access control program for X
xinetd
The extended Internet services daemon.
xload
System load average display for X.
xlsfonts
Server font list displayer for X.
xmms
Audio player for X.
xpdf
PDF viewer.
xterm
Terminal emulator for X.
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Z zcat
Compress or expand files.
zgrep zmore
Search possibly compressed files for a regular expression.
Filter for viewing compressed text.
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