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
sftp : secure file transfer program
openssl : OpenSSL command line tool
...

shell

busybox : The Swiss Army Knife of Embedded Linux
gnome-terminal : is a terminal emulation application.
which : locate a command
fusermount : mount and unmount FUSE filesystems
watch : execute a program periodically, showing output fullscreen
locale : specific information.
...

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
mkfs : build a Linux filesystem
rename : renames multiple files
...

programming

strace : trace system calls and signals
MAKEDEV : create devices
busybox : The Swiss Army Knife of Embedded Linux
startpar : start runlevel scripts in parallel
javaws : a Java Web Start client
iconv : Convert encoding of given files from one encoding to another
...

file

passwd : change user password
su : change user ID or become superuser
mkfs.ext2 : create an ext2/ext3/ext4 filesystem
egrep : , fgrep, rgrep print lines matching a pattern
hexdump : , hd ASCII, decimal, hexadecimal, octal dump
rm : remove files or directories
...

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
update-grub : stub for grub-mkconfig
time : run programs and summarize system resource usage
avconv : avconv video converter
getconf : Query system configuration variables
...

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

update-grub : stub for grub-mkconfig
pk2bm : create a bitmap from a TeX pkfont
dvdrip : GUI for copying DVDs
pdb3.3 : the Python debugger
bzip2 : recover recovers data from damaged bzip2 files
nohup : run a command immune to hangups, with output to a non-tty
...

printer

ppdc : cups ppd compiler
ghostscript : Ghostscript (PostScript and PDF language interpreter and previewer)
sldtoppm : convert an AutoCAD slide file into a portable pixmap
lprm : cancel print jobs
sensible-pager : pager, sensible-browser - sensible editing, paging, and web browsing
cweave : translate CWEB to C and/or TeX
...

text manipulation

passwd : change user password
start-stop-daemon : start and stop system daemon programs
cut : remove sections from each line of files
grep : print lines matching a pattern
chcon : change file security context
airtun-ng : a virtual tunnel interface creator for aircrack-ng
...

privacy

passwd : change user password
tor-gencert : Generate certs and keys for Tor directory authorities
lame : create mp3 audio files
start-stop-daemon : start and stop system daemon programs
wpa_passphrase : Generate a WPA PSK from an ASCII passphrase for a SSID
gpgsplit : Split an OpenPGP message into packets
...

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
gst-launch-1.0 : build and run a GStreamer pipeline
dh_installppp : install ppp ip-up and ip-down files
airtun-ng : a virtual tunnel interface creator for aircrack-ng
usermod : modify a user account
login : begin session on the system
...

file compression

pdb3.3 : the Python debugger
scp-dbus-service :
file-roller : archive manager for GNOME
lzcat : Compress or decompress .xz and .lzma files
airtun-ng : a virtual tunnel interface creator for aircrack-ng
nohup : run a command immune to hangups, with output to a non-tty
...

boot settings

tcmp3cut :
erb1.8 : an embedded Ruby language interpreter
start-stop-daemon : start and stop system daemon programs
ping : 6 send ICMP ECHO_REQUEST to network hosts
showkey : examine the codes sent by the keyboard
dbus-send : Send a message to a message bus
...

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
loadunimap : load the kernel unicode-to-font mapping table
pdb3.3 : the Python debugger
sha1sum : compute and check SHA1 message digest
nohup : run a command immune to hangups, with output to a non-tty
ping : 6 send ICMP ECHO_REQUEST to network hosts
...

font

mft : translate Metafont or MetaPost code to TeX code for prettyprinting
airtun-ng : a virtual tunnel interface creator for aircrack-ng
update-grub : stub for grub-mkconfig
alias :
pdb3.3 : the Python debugger
iconv : Convert encoding of given files from one encoding to another
...

mail

nohup : run a command immune to hangups, with output to a non-tty
ping : 6 send ICMP ECHO_REQUEST to network hosts
start-stop-daemon : start and stop system daemon programs
avconv : avconv video converter
jack_connect : JACK toolkit clients for connecting & disconnecting ports
airtun-ng : a virtual tunnel interface creator for aircrack-ng
...

Media Player

airtun-ng : a virtual tunnel interface creator for aircrack-ng
loadunimap : load the kernel unicode-to-font mapping table
pdb3.3 : the Python debugger
iconv : Convert encoding of given files from one encoding to another
python2.7 : an interpreted, interactive, object-oriented programming language
lame : create mp3 audio files
...

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
...

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