What are the Basic Unix Commands?

The total number of Unix commands is immense. No normal user or system administrator would ever need to know them all.

The Unix commands available to you will vary based upon several factors:

The version of Unix you are using (FreeBSD, Linux, Solaris, AIX, HP-UX, OpenBSD, etc...)
The Unix shell you are using (sh, csh, tcsh, ksh, bash, etc...)
The packages installed on the system and the way the system is configured
Your access level on the system

In this FAQ, I will address only Bash shell commands, as all other major shells can now be considered obsolete.

This list of basic Unix commands will get you started using and learning Unix.

Use the Unix `man` command to learn more about any of these commands.

Basic Unix Commands

Unix Command	Description
ls	List directory contents
cp	Copy files
rm	Remove directory entries
file	Determine file type
find	Walk a file hierarchy
which	Locate a program file in the user's path
whereis	Locate programs
gcc, g++	GNU project C and C++ Compiler
gdb	The GNU Debugger
less	View the contents of a text file
diff	Find differences between two files
cmp	Compare two files
vi	Text editor
chmod	Change file modes
man	Display the on-line manual pages
mv	Move and rename files
ispell	Interactive spelling checker
biff	Be notified if mail arrives and who it is from
lpr	Print a file
lpq	Show the print queue
ftp	Transfer a file to another Unix system
logout	Quit using the system
pwd	Print working directory name
cd	Change working directory
ln	Make a file link
mkdir	Make directories
rmdir	Remove directories
chmod	Change file modes
quota	Display disk usage and limits
history	Display a list of recent commands
ps	Show the status of processes
kill	Stop a running processes
passwd	Change your password
alias	Create a command alias
unalias	Delete a command alias
export	Set an environment variable
script	Record your terminal session to a file
bg	Send a job to the background
fg	Bring a job to the foreground
jobs	Print a list of current jobs

The basic Unix commands are fairly standard across the various Unix platforms, although command arguments differ at times. In addition, the basic Unix commands vary between Unix shells.

Learning the Unix Operating System

If you're new to Unix, this concise book will tell you just what you need to get started and no more. This fifth edition is the most effective introduction to Unix in print, covering Internet usage for email, file transfers, and web browsing. It's an ideal primer for Mac and PC users who need to know a little about Unix on the systems they visit. The new edition also contains many major and minor updates to help the reader navigate Unix's ever-expanding capabilities. In response to the popularity of Linux, the book now focuses on the popular bash shell preferred by most Linux users. A new chapter explains how to use ftp, pine for mail, and offers useful knowledge on how to surf the web. And the author has included tips throughout the text on security basics, especially in the Internet and networking sections. The book includes a completely updated quick reference card to make it easier for the reader to access the key functions of the command line.