Bash

Core Commands

Key/Command	Description
cd [folder]	Change directory e.g. cd Documents
cd	Home directory
cd ~	Home directory
cd /	Root of drive
cd -	Previous directory
ls	Short listing (just names)
ls -l	Long listing (names + extra info)
ls -a	Listing incl. hidden files
ls -lh	Long listing with Human readable file sizes
ls -R	Entire content of folder recursively
sudo [command]	Run command with the security privileges of the superuser (Super User DO)
open [file]	Opens a file ( as if you double clicked it )
top	Displays active processes. Press q to quit
nano [file]	Opens the file using the nano editor
vim [file]	Opens the file using the vim editor
clear	Clears the screen
reset	Resets the terminal display

Chaining Commands

Key/Command	Description
[command-a]; [command-b]	Run command A and then B, regardless of success of A
[command-a] && [command-b]	Run command B if A succeeded
[command-a] || [command-b]	Run command B if A failed
[command-a] &	Run command A in background

Command History

Key/Command	Description
history n	Shows the stuff typed – add a number to limit the last n items
Ctrl + r	Interactively search through previously typed commands
![value]	Execute the last command typed that starts with ‘value’
![value]:p	Print to the console the last command typed that starts with ‘value’
!!	Execute the last command typed
!!:p	Print to the console the last command typed

File Management

Key/Command	Description
touch [file]	Create a new file
pwd	Full path to working directory
.	Current folder, e.g. ls .
..	Parent/enclosing directory, e.g. ls ..
ls -l ..	Long listing of parent directory
cd ../../	Move 2 levels up
cat	Concatenate to screen
rm [file]	Remove a file, e.g. rm data.tmp
rm -i [file]	Remove with confirmation
rm -r [dir]	Remove a directory and contents
rm -f [file]	Force removal without confirmation
cp [file] [newfile]	Copy file to file
cp [file] [dir]	Copy file to directory
mv [file] [new filename]	Move/Rename, e.g. mv file1.ad /tmp
pbcopy < [file]	Copies file contents to clipboard
pbpaste	Paste clipboard contents
pbpaste > [file]	Paste clipboard contents into file, pbpaste > paste-test.txt

Directory (Folder) Management

Key/Command	Description
mkdir [dir]	Create new directory
mkdir -p [dir]/[dir]	Create nested directories
rmdir [dir]	Remove directory ( only operates on empty directories )
rm -R [dir]	Remove directory and contents
less [file]	Output file content delivered in screensize chunks
[command] > [file]	Push output to file, keep in mind it will get overwritten
[command] >> [file]	Append output to existing file
[command] < [file]	Tell command to read content from a file

Search

Key/Command	Description
find [dir] -name [search_pattern]	Search for files, e.g. find /Users -name "file.txt"
grep [search_pattern] [file]	Search for all lines that contain the pattern, e.g. grep "Tom" file.txt
grep -r [search_pattern] [dir]	Recursively search in all files in specified directory for all lines that contain the pattern
grep -v [search_pattern] [file]	Search for all lines that do NOT contain the pattern
grep -i [search_pattern] [file]	Search for all lines that contain the case-insensitive pattern
mdfind [search_pattern]	Spotlight search for files (names, content, other metadata), e.g. mdfind skateboard
mdfind -onlyin [dir] -name [pattern]	Spotlight search for files named like pattern in the given directory

Shortcuts

Key/Command	Description
Ctrl + A	Go to the beginning of the line you are currently typing on.
Ctrl + E	Go to the end of the line you are currently typing on.
Ctrl + L	Clears the Screen
Cmd + K	Clears the Screen
Ctrl + U	Cut everything backwards to beginning of line
Ctrl + K	Cut everything forward to end of line
Ctrl + W	Cut one word backwards using white space as delimiter
Ctrl + Y	Paste whatever was cut by the last cut command
Ctrl + H	Same as backspace
Ctrl + C	Kill whatever you are running. Also clears everything on current line
Ctrl + D	Exit the current shell when no process is running, or send EOF to a the running process
Ctrl + Z	Puts whatever you are running into a suspended background process. fg restores it
Ctrl + _	Undo the last command. (Underscore. So it's actually Ctrl + Shift + minus)
Ctrl + T	Swap the last two characters before the cursor
Ctrl + F	Move cursor one character forward
Ctrl + B	Move cursor one character backward
Option + →	Move cursor one word forward
Option + ←	Move cursor one word backward
Esc + T	Swap the last two words before the cursor
Esc + Backspace	Cut one word backwards using none alphabetic characters as delimiters
Tab	Auto-complete files and folder names

Help

Key/Command	Description
[command] -h	Offers help
[command] --help	Offers help
info [command]	Offers help
man [command]	Show the help manual for [command]
whatis [command]	Gives a one-line description of [command]
apropos [search-pattern]	Searches for command with keywords in description

Misc:

• awk - basically a general-purpose scripting language designed mostly used for printing.

• sed - 'stream editor' used for file operations like searching, find and replace, insertion or deletion.

• lsof - 'list open files' gives the info to find out the files which are opened by which process.

• curl - used for transferring data from/to a server designed to work without user interaction

• wget - used for downloading files from the web

  • provides a number of options allowing you to download multiple files, resume downloads, limit the bandwidth, recursive downloads, download in the background, mirror a website, and much more

• tail - print the last N number of data of the file; by default it prints the last 10 lines.

• head - print the first N number of data of the file; by default it prints the first 10 lines.

• ssh - 'secure shell' protocol used to securely connect to a remote server/system

  • transfers the data in encrypted form between host and client. SSH runs at TCP/IP port 22

• kill - used to terminate processes manually; sends a signal to a process which terminates the process