The following table shows the keyboard shortcuts or combinations of keys that provide an alternative way to do something that you'd typically do with a mouse.

Use these keys or keys in combination	To do this
Command + A	Select all items in a document or window.
Command + C	Copy the selected item to the clipboard.
Command + Control + D	Look up selected word in the dictionary or thesaurus.
Command + F	Find items in a document or open a Find window.
Command + G	Find the next occurrence of the item previously found.
Command + Shift + G	Find the previous occurrence of the item just found.
Command + H	Hide the windows of the front app.
Command + Option + H	To view the front application but hide all other apps.
Command + M	Minimize the front window to the Dock.
Command + Option + M	Minimize all windows of the front app.
Command + N	Open a New document or window.
Command + O	Open the selected item, or open a dialog to select a file to open.
Command + P	Print the current document.
Command + Q	Quit the app.
Command + S	Save the current document.
Command + T	Opens a new tab on your web browser.
Command + V	Paste the Clipboard contents into the current document or app.
Command + W	Close the front window.
Command + Option + W	Close all windows of the app.
Command + X	Cut the selected item and copy it to the Clipboard.
Command + Z	Undo the previous command.
Command + Shift + Z	Redo the previous command.
Command + Shift + 3	Take a screenshot of the entire screen.
Command + Shift + 4	Take a screenshot of just part of the screen.
Command + Comma(,)	Open preferences for the front app.
Command + Option + Esc	Choose an app to force quit.
Command + Shift + Option + Esc	Hold for 3 seconds to force just the front app to quit.
Command + Spacebar	Show or hide the Spotlight search field.
Command + Option + Spacebar	Show or hide the Spotlight search field from a Finder window.
Command + Tab	Switch to the next most recently used app among the open apps.
Command + Shift + Tilde(~)	Switch to the next most recently used window of the front app.
Option + Spacebar	Types a non-breaking space between words such that both words always display on the same line. In MS Word (and some other apps) it displays as '°' when paragraph marks are showing.
Shift + Enter	Inserts a line break within a paragraph. In MS Word (and some other apps) it displays as '' when paragraph marks are showing.