Unix, Linux, and variants

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Unix ABCs
Linux ABCs
MS-DOS vs. Linux and Unix
Unix and Linux commands
Unix Top 10 commands
Unix Shortcuts
Unix and Linux history
Unix and Linux tips
Unix and Linux links
Linux Q&A

Unix ABCs

Unix, which is not an acronym, was developed in the late 1960's by many of the same people who helped create the C programming language. Today, however, Unix is not just the work of a couple of programmers. Other organizations, institutes, and individuals contributed significant additions to the modern Unix system.

  • See our Unix definition for additional related information.

Linux ABCs

Linux (pronounced "lee'nuhks" or li'nuks, but not li'nuhks) is the kernel of a free, open source operating system. The Linux kernel was developed by Linus Torvalds and released in 1991. It provided the underlying foundations for an operating system, but it lacked the user-level tools to make it complete.

The GNU project, begun in 1984 by Richard Stallman, had similar aims, creating a set of open source tools and utilities modeled on the closed-source Unix operating system. The GNU project lacked an underlying kernel, however. After the Linux kernel was released, contributors ported GNU tools to the Linux kernel, and the GNU/Linux operating system was born.

There is significant controversy (even today) over whether to refer to this combined operating system as "GNU/Linux" or "Linux." However, the general populace has gravitated to the name "Linux," and this name has largely stuck. The contributions of the GNU project must not be overlooked, however. Whenever you run an essential command in Linux, you are using a tool painstakingly created by members of the GNU project.

Over the years, Linux kernel development has grown to a group of over 10,000 developers all over the world. It is released under General Public License (GPL): it can be distributed, used, and expanded free of charge, and developers have access to all the source code.

  • See our Linux definition for related information and variant information.

MS-DOS vs. Linux and Unix

If you can navigate a computer using MS-DOS or the Windows command line, you should be able to quickly pick up on the navigation of Linux and Unix. In the below chart is a listing of common MS-DOS commands with their Linux and Unix counterpart.

MS-DOS Linux and Unix
attrib chmod
backup tar
dir ls
cls clear
copy cp
del rm
deltree rm -R
rmdir
edit vi
pico
format fdformat, mount, and umount
move and rename mv
Type less <file>
cd cd
chdir
more < file more file
md mkdir
win startx

Linux and Unix Commands

  * See the Linux and Unix overview page for a brief description on all commands on one page.
A a2p | ac | addgroup | adduser | alias | agrep | apropos | apt-cache | apt-get | aptitude | ar | arch | arp | as | aspell | at | atq | atrm | awk
B basename | bash | batch | bc | bdiff | bfs | bg | biff | break | bs | bye
C cal | calendar | cancel | cat | cc | cd | cfdisk | chdir | checkeq | checknr | chfn | chgrp | chkey | chmod | chown | chroot | chsh | cksum | clear | cls | cmp | col | comm | compress | continue | copy | cp | cpio | crontab | csh | csplit | ctags | cu | curl | cut
D date | dc | dd | df | delgroup | deluser | depmod | deroff | dhclient | diff | dig | dircmp | dirname | dmesg | dos2unix | dpkg | dpost | du
E echo | ed | edit | egrep | eject | elm | emacs | enable | env | eqn | ex | exit | expand | expr
F fc | fdisk | fg | fgrep | file | find | findsmb | finger | fmt | fold | for | foreach | free | fromdos | fsck | ftp | fuser
G gawk | getfacl | gpasswd | gprof | grep | groupadd | groupdel | groupmod | gunzip | gview | gvim | gzip
H halt | hash | hashstat | head | help | history | host | hostid | hostname
I id | ifconfig | ifdown | ifup | ip | init | info | insmod | iostat | isalist | iwconfig
J jobs | join
K keylogin | kill | killall | ksh
L last | ld | ldd | less | lex | link | ln | lo | locate | login | logname | logout | losetup | lp | lpadmin | lpc | lpq | lpr | lprm | lpstat | ls | lsof | lsmod| lzcat | lzma
M mach | mail | mailcompat | mailx | make | man | merge | mesg | mii-tool | mkdir | mkfs | mkswap | modinfo | modprobe | more | mt | mv | myisamchk | mysql | mysqldump
N nc | neqn | netstat | newalias | newform | newgrp | nice | niscat | nischmod | nischown | nischttl | nisdefaults | nisgrep | nismatch | nispasswd | nistbladm | nl | nmap | nohup | nroff | nslookup
O od | on | onintr | optisa
P pack | pagesize | parted | partprobe | passwd | paste | pax | pcat | perl | pg | pgrep | pico | pine | ping | pkill | poweroff | pr | printenv | priocntl | printf | ps | pstree | pvs | pwd | python
Q quit
R rcp | readlink | reboot | red | rehash | remsh | rename | renice | repeat | replace | rgview | rgvim | rlogin | rm | rmail | rmdir | rmmod | rn | route | rpcinfo | rsh | rsync | rview | rvim
S s2p | sag | sar | scp | screen | script | sdiff | sed | sendmail | service | set | setenv | setfacl | sfdisk | sftp | sh | shred | shutdown | signals | sleep | slogin | smbclient | sort | spell | split | stat | stop | startx | strftime | strip | stty | su | sudo | swapoff | swapon | sysklogd
T tabs | tac | tail | talk | tar | tbl | tcopy | tcpdump | tcsh | tee | telinit | telnet | test | time | timex | todos | top | touch | tput | tr | traceroute | tree | troff | tty
U ulumask | unalias | uname | uncompress | unhash | uniq | unlink | unlzma | unmount | unpack | untar | until | unxz | unzip | uptime | useradd | userdel | usermod
V vacation | veditvgrind | vi | view | vim | vipw | visudo | vmstat
W w | wait | wall | wc | wget | whereis | whatis | which  | while| who | whoami | whois | write
X X | xargs | xfd | xhost | xinit | xlsfonts | xorg | xset | xterm | xrdb | xz | xzcat
Y yacc | yes | yppasswd | yum
Z zcat | zip | zipcloak | zipinfo | zipnote | zipsplit

Tip: Additional information about a specified command for your Unix or Linux variant can be found by using the man command.