Mac and Linux Shortcut Keys

Shortcut Keys Description 
Open Apple + Down Opens the selected icon.
Shift + Click Select the icon and add it to the set of those selected.
Tab Highlight the next icon inside the folder, in alphabetical order.
Shift + Tab Highlight the previous icon inside the folder, in alphabetical order.
Left arrow Used when viewing by icon to select the icon to the left of the one highlighted.
Right arrow Used when viewing by icon to select icon to the right of the one highlighted.
Up arrow Used to select the icon above the one currently highlighted.
Down arrow Used to select the icon below the one currently highlighted.
Open Apple + ? Mac help
Open Apple + E Eject
Open Apple + Shift + Up Arrow Used to direct the input focus to the desktop level.
Open Apple + M Minimize window
Open Apple + N New finder window
Open Apple + Shift + N New folder
Open Apple + W Close the current window.
Open Apple + C Copy the elected item to the clipboard.
Open Apple + X Cut the selected item.
Open Apple + V Paste item from the clipboard
Open Apple + L Make alias
Open Apple + R Show original item
Open Apple + T Add to favorites
Open Apple + O Open the selected icon.
Open Apple + F Display the find dialog box.
Open Apple + G Repeat the last find operation.
Open Apple + Shift + G Takes a snapshot of the screen and saves it to a PICT file.

(Please note that not all of the below shortcut keys will work in all versions of Mac OS)

Linux shortcut keys
Shortcut keys  Description 
CTRL + B Moves the cursor backward one character.
CTRL + C Cancels the currently running command.
CTRL + D Logs out of the current session.
CTRL + F Moves the cursor forward one character.
CTRL + H Erase one character. Similar to pressing backspace.
CTRL + P Paste previous line and/or lines.
CTRL + S Stops all output on screen (XOFF).
CTRL + Q Turns all output stopped on screen back on (XON).
CTRL + U Erases the complete line.
CTRL + W Deletes the last word typed in. For example, if you typed ‘mv file1 file2’ this shortcut would delete file2.
CTRL + Z Cancels current operation, moves back a directory and/or takes the current operation and moves it to the background. See bg command for additional information about background.
Linux Command line shortcut keys
 Shortcut keys Description 
~ Moves to the user’s home directory.
!! Repeats the line last entered at the shell. 
!$ Repeats the last argument for the command last used. 
reset Resets the terminal if terminal screen is not displaying correctly.
shutdown -h now Remotely or locally shuts the system down.
adduser Add a user to the system
alias Create an alias 
chmod Change access permissions
echo Display message on screen 
mv Move or rename files or directories
mount Mount a file system
man Help manual
killall Kill processes by name
passwd Modify a user password
su Substitute user identity

Remotely or locally shuts the system down.