network

netcat : NC(1) BSD General Commands Manual NC(1) nc — arbitrary TCP and UDP connections and listens
ping : 6 send ICMP ECHO_REQUEST to network hosts
nmcli : – commandline tool for controlling NetworkManager
telnet : user interface to the TELNET protocol
openssl : OpenSSL command line tool
sftp : secure file transfer program
...

shell

busybox : The Swiss Army Knife of Embedded Linux
gnome-terminal : is a terminal emulation application.
watch : execute a program periodically, showing output fullscreen
locale : specific information.
startpar : start runlevel scripts in parallel
xargs : build and execute command lines from standard input
...

filesystem

resize2fs : ext2/ext3/ext4 file system resizer
fsck : check and repair a Linux filesystem
chown : change file owner and group
passwd : change user password
aireplay-ng : inject packets into a wireless network to generate traffic
fsck.ext4 : check a Linux ext2/ext3/ext4 file system
...

programming

strace : trace system calls and signals
MAKEDEV : create devices
busybox : The Swiss Army Knife of Embedded Linux
startpar : start runlevel scripts in parallel
find : search for files in a directory hierarchy
killall5 : - send a signal to all processes.
...

file

mkfs.ext2 : create an ext2/ext3/ext4 filesystem
egrep : , fgrep, rgrep print lines matching a pattern
hexdump : , hd ASCII, decimal, hexadecimal, octal dump
passwd : change user password
su : change user ID or become superuser
fsck.ext3 : check a Linux ext2/ext3/ext4 file system
...

graphic manipulation

gimp : an image manipulation and paint program.
start-stop-daemon : start and stop system daemon programs
bmp2tiff : create a TIFF file from a Microsoft Windows Device Independent Bitmap image file
MAKEDEV : create devices
debugfs : ext2/ext3/ext4 file system debugger
djpeg : decompress a JPEG file to an image file
...

database

mysqlimport : a data import program
mysqld_safe : MySQL server startup script
find : search for files in a directory hierarchy
mysql_zap : kill processes that match a pattern
gnome-terminal.wrapper : is a terminal emulation application.
airtun-ng : a virtual tunnel interface creator for aircrack-ng
...

X

gnome-terminal : is a terminal emulation application.
xfreerdp : FreeRDP X11 client
xlsclients : list client applications running on a display
lame : create mp3 audio files
loadunimap : load the kernel unicode-to-font mapping table
pnmmargin : add a border to a portable anymap
...

package management

dpkg-reconfigure : reconfigure an already installed package
apt-config : APT Configuration Query program
passwd : change user password
cweave : translate CWEB to C and/or TeX
python2.7 : an interpreted, interactive, object-oriented programming language
dh_installdeb : install files into the DEBIAN directory
...

printer

ppdc : cups ppd compiler
ghostscript : Ghostscript (PostScript and PDF language interpreter and previewer)
passwd : change user password
lpadmin : configure cups printers and classes
cups-calibrate : ESP CUPS Printer Calibration Tool
smbspool : send a print file to an SMB printer
...

text manipulation

dvipdf : Convert TeX DVI file to PDF using ghostscript and dvips
tac : concatenate and print files in reverse
iconv : Convert encoding of given files from one encoding to another
bluez-simple-service :
unwrapdiff : demangle word-wrapped patches
fmtutil-sys : utility for maintaining TeX format files system-wide
...

privacy

passwd : change user password
airtun-ng : a virtual tunnel interface creator for aircrack-ng
update-grub : stub for grub-mkconfig
avconv : avconv video converter
pdb3.3 : the Python debugger
gzexe : compress executable files in place
...

sound manipulation

gst-launch-1.0 : build and run a GStreamer pipeline
audacity : Graphical cross-platform audio editor
start-stop-daemon : start and stop system daemon programs
ogmsplit : Split OGG/OGM files into several smaller OGG/OGM files
sndfile-metadata-set : set metadata in a sound file
spd-conf : A simple tool for basic configuration of Speech Dispatcher and problem diagnostics
...

Access Control List

su : change user ID or become superuser
MAKEDEV : create devices
update-grub : stub for grub-mkconfig
uic :
start-stop-daemon : start and stop system daemon programs
nohup : run a command immune to hangups, with output to a non-tty
...

file compression

avconv : avconv video converter
xzgrep : search compressed files for a regular expression
start-stop-daemon : start and stop system daemon programs
filterdiff : extract or exclude diffs from a diff file
p7zip : Wrapper on 7zr, a 7-zip file archiver with high compression ratio
lame : create mp3 audio files
...

boot settings

dh_installppp : install ppp ip-up and ip-down files
kerneloops : program to collect and submit kernel oopses to kerneloops.org
cweave : translate CWEB to C and/or TeX
grub-mkimage : make a bootable image of GRUB
passwd : change user password
spd-conf : A simple tool for basic configuration of Speech Dispatcher and problem diagnostics
...

text editor

pdb3.3 : the Python debugger
cweave : translate CWEB to C and/or TeX
cpp : The C Preprocessor
kerneloops : program to collect and submit kernel oopses to kerneloops.org
update-grub : stub for grub-mkconfig
gedit : text editor for the GNOME Desktop
...

webserver

a2ensite : enable or disable an apache2 site / virtual host
apachectl : Apache HTTP server control interface
cweave : translate CWEB to C and/or TeX
gemtopnm : convert a GEM .img file into a portable anymap
airtun-ng : a virtual tunnel interface creator for aircrack-ng
update-grub : stub for grub-mkconfig
...

font

spd-conf : A simple tool for basic configuration of Speech Dispatcher and problem diagnostics
debugfs : ext2/ext3/ext4 file system debugger
ofm2opl : convert Omega and TeX font-metric files to property-list files
passwd : change user password
cweave : translate CWEB to C and/or TeX
mft : translate Metafont or MetaPost code to TeX code for prettyprinting
...

mail

thunderbird : Mail User Agent (MUA) and newsgroup/RSS client for X11 derived from the Mozilla suite.
update-grub : stub for grub-mkconfig
pdb3.3 : the Python debugger
sha1sum : compute and check SHA1 message digest
logrotate : rotates, compresses, and mails system logs
lame : create mp3 audio files
...

Media Player

spd-conf : A simple tool for basic configuration of Speech Dispatcher and problem diagnostics
update-grub : stub for grub-mkconfig
passwd : change user password
cweave : translate CWEB to C and/or TeX
avifix : fix header of AVI-file
airtun-ng : a virtual tunnel interface creator for aircrack-ng
...

virtualization

nohup : run a command immune to hangups, with output to a non-tty
passwd : change user password
cweave : translate CWEB to C and/or TeX
avconv : avconv video converter
airtun-ng : a virtual tunnel interface creator for aircrack-ng
update-grub : stub for grub-mkconfig
...

help us categorise commands