Command-line cheat sheet

This page lists the most common commands in the Ubuntu command line. For full details on any command, run man <command> in your terminal.

CLI basics

More detailed explanation of the commands in this section can be found in our Welcome to the terminal tutorial.

Navigation

Command	Description	Online manual page
pwd	Print the current working directory	pwd(1)
ls	List all files and directories in the current directory	ls(1)
ls -l	Long list, with permissions, owner, size, and date
ls -a	List all, including hidden files (file names starting with .)
ls -la or ll	Long listing including hidden files
ls -ld <dir>	Show the directory entry itself, not its contents, for directory <dir>
ls -l <file>	Show file type, permissions, owner, and size for <file>
cd <path>	Change to the specified directory	cd(1posix)
cd ..	Move up to the parent directory
cd ~	Return to the home directory
cd -	Return to the previous directory
cd /	Move to the root directory
cd ../../	Move up two levels at once

Working with the filesystem

Command	Description	Online manual page
mkdir <name>	Create a new directory	mkdir(1)
rmdir <name>	Remove an empty directory	rmdir(1)
tree	Display directory structure as a tree	tree(1)
tree -L <n> <path>	Display tree to depth n

Working with files

Command	Description	Online manual page
touch <file>	Create a new (empty) file, or update the timestamp of an existing file	touch(1)
cp <src> <dest>	Copy a file from a source (src) to a new destination (dest)	cp(1)
cp -a <src> <dest>	Copy a directory recursively, preserving permissions
mv <src> <dest>	Rename a file or directory	mv(1)
mv <src>/file <dest>/file	Move a file without renaming it
rm <file>	Remove a file	rm(1)
rm -r <dir>	Remove a non-empty directory and all its contents
cat <file>	Print the contents of <file> to the screen	cat(1)
less <file>	View file contents one page at a time	less(1)
head -n 20 <file>	Print the first 20 lines of a file (default with no flag is 10)	head(1)
tail -n 20 <file>	Print the last 20 lines of a file (default with no flag is 10)	tail(1)
wc -l <file>	Count the number of lines in a file	wc(1)

Users, groups, and permissions

Command	Description	Online manual page
chmod <mode> <file>	Change file permissions (symbolic or numeric notation)	chmod(1)
chown <user>:<group> <file>	Change file owner and group	chown(1)
umask	Show or set the default permissions mask	umask(2)
sudo <command>	Run a command with administrator privileges	sudo(8)

Searching

Command	Description	Online manual page
grep <pattern> <file>	Search for lines matching a pattern in a file	grep(1)
grep <name> /etc/passwd	Look up a user account
grep <name> /etc/group	Look up group membership
find <path> -name <pattern>	Search for files matching a name pattern	find(1)
which <command>	Show the full path to an executable command	which(1)
file <name>	Determine the type of a file	file(1)

CLI in depth

More detailed explanation of the commands and operators in this section can be found in our The command line in depth tutorial.

Redirecting input and output

Command	Description
cmd > file	Redirect stdout (1) to a file (overwrites existing content)
cmd >> file	Append stdout (1) to the end of <file> (does not overwrite existing contents)
cmd < file	Pass a file’s contents as stdin (0) to a command (cmd)
cmd > /dev/null	Discard stdout (1) entirely
cmd 2> file	Redirect stderr (2) to a file
cmd > file 2>&1	Redirect both stdout (1) and stderr (2) to a file
cmd << EOF	Here-document: feed multi-line text as stdin, ended by a line containing EOF

Pipes and command chaining

Command	Description
cmd1 | cmd2	Pipe stdout (1) of cmd1 to stdin (0) of cmd2
cmd1; cmd2	Run commands in sequence regardless of exit status
cmd1 && cmd2	Run cmd2 only if cmd1 succeeds (exit code 0)
cmd1 || cmd2	Run cmd2 only if cmd1 fails (non-zero exit code)
cmd &	Run a command in the background
{ cmd1; cmd2; } > file	Group commands and redirect their combined output
(cmd1; cmd2)	Run commands in a subshell (side effects don’t affect the current shell)
cmd1 \	Continue a long command on the next line

Variables and environment

Command	Description	Online manual page
env	List all environment variables	env(1)
echo $VAR	Print the value of variable VAR	See note below this table
VAR=value	Set a shell variable (available in current shell only)
export VAR=value	Set a variable and export it to child processes
unset VAR	Remove a variable
echo $?	Print the exit status of the last command (0 = success)
echo $$	Print the PID of the current shell

Note

If you are using the bash, dash or zsh shell, echo is a builtin command documented under the shell manual page. For example, the bash builtin shell section. If your shell doesn’t have an echo builtin command, use the echo(1) manual page instead.

Shell expansion

Command	Description
~	Expands to the home directory ($HOME)
$VAR, ${VAR}	Variable expansion: replaced by the value of VAR
$(command)	Command substitution: replaced by the output of command
$((expr))	Arithmetic expansion: evaluates integer arithmetic, e.g. $((5 + 3)) evaluates to 8
{a,b,c}	Brace expansion: generates separate words, e.g. {a,b,c} → a b c
{1..10}	Range expansion: generates a sequence, e.g. {1..5} → 1 2 3 4 5
*	Glob: matches any sequence of characters in a filename
?	Glob: matches any single character in a filename
[abc]	Glob: matches any one of the listed characters in a filename

Getting help

Command	Description	Online manual page
man <command>	Open the manual page for a command
man man	Open the manual page for man itself	man(1)
man -k <keyword>	Search man page descriptions for a keyword
<command> --help	Print a brief help summary for a command