Quit all apps, then restart your Mac. If any open documents have unsaved changes, you'll be asked whether you want to save them

Move the selected item to the Trash

Capture a portion of the screen

Type an Apple icon

Open Screenshot app

Take a screenshot of the entire screen

Log out of your macOS user account. You'll be asked to confirm

Undo the previous command. You can then press Command + Shift + Z to Redo, reversing the undo command. In some apps, you can undo and redo multiple commands

Hide the windows of the front app. To view the front app but hide all other apps, press Command + Option + H

Empty the Trash without confirmation dialog

Press and hold for 1.5 seconds while your Mac is awake to display a dialog asking if you want to sleep, restart, or shut down. If you don't want to wait 1.5 seconds, press Control (Plus) Power button or Control (Plus) Media Eject

Put your displays to sleep

Delete the character to the right of the insertion point. Or use Fn + Delete

Forward delete on keyboards that don't have a Forward Delete  key. Or use Control + D

Delete the word to the left of the insertion point

Swap the character behind the insertion point with the character in front of the insertion point

Turn display mirroring on or off when your Mac is connected to more than one display

Open a Go to Folder window

Open the Computer window

Show or hide the inspector window

Copy the formatting settings of the selected item to the Clipboard

Open the Network window

Apply the style of the surrounding content to the item pasted within that content

Open the Connect to Server window

Open the All My Files window

Move the files in the Clipboard from their original location to the current location

Apply the copied style to the selected item

Display a window for selecting document settings

Display the Save As dialog, or duplicate the current document

Open the desktop folder

Show or hide the Spotlight search field. To perform a Spotlight search from a Finder window, press Command + Option + Space. If you use multiple input sources to type in different languages, these shortcuts change input sources instead of showing Spotlight

Cut the selected item and copy it to the Clipboard

Log out of your macOS user account immediately, without being asked to confirm

Move the insertion point to the beginning of the previous word

Go to the search field

(on a window title) See the folders that contain the current folder

Open a folder in a separate window and close the current window

Empty the Trash

Open Mission Control preferences

(legacy) Eject external floppy disk

Open the Downloads folder

Duplicate the selected files

Hide or show the Sidebar in Finder windows

Add selected Finder item to the Dock (OS X Mountain Lion or earlier)

Show View Options

Force your Mac to restart

Switch to the next most recently used app among your open apps

Put your displays to sleep

Save the current document

Quit the app

Choose an app to force quit. Or press Command + Shift + Option + Esc and hold for 3 seconds to force just the front app to quit

Minimize the front window to the Dock. To minimize all windows of the front app, press Command + Option + M

Arrow Extend text selection to the beginning of the current word, then to the beginning of the following word if pressed again

Scroll down one page

Scroll to the beginning of a document

Display the Spelling and Grammar window

Find misspelled words in the document

Hide or show the path bar in Finder windows

Create a new folder

Open the folder that contains the current folder.

Show or hide a toolbar in the app

Open a folder in a separate tab or window

Capture a window or menu

Use Quick Look to preview the files

Right align

Move one character forward

Move up one line

Move down one line

Start a Spotlight search in the Finder window

Show the Get Info window for a selected file

Arrow Extend text selection to the end of the current paragraph, then to the end of the following paragraph if pressed again

Increase the size of the selected item. Command–Equal sign (=) performs the same function.

Open the Documents folder

Control Show the desktop. This works even when you're not in the Finder

Show or hide the toolbar when a single tab is open in the current Finder window

Close the selected folder. This works only when in list view

View the items in a Finder window with Cover Flow

Use Quick Look to preview the selected files

Show the original file for the selected alias

Open iCloud Drive

Italicize the selected text, or turn italics on or off

Underline the selected text, or turn underlining on or off

Select the text between the insertion point and the beginning of the current line

Move the insertion point to the end of the next word

Move the insertion point to the beginning of the current line

Move the insertion point to the end of the current line

Close the front window. To close all windows of the app, press Command + Option + W.

Take a screenshot

Open the AirDrop window

Open the Home folder of the current macOS user account

Show or hide the definition of the selected word

(legacy) Eject internal floppy disk

Press to turn on your Mac or wake your Mac from sleep

View a Quick Look slideshow of the selected files

Go to the previous folder

Go to the next folder

View the items in the Finder window as icons

View the items in a Finder window as a list

View the items in a Finder window in columns

Open the selected folder. This works only when in list view

Turn Target Display Mode on or off

Arrow  Open the folder that contains the current folder in a new window

Open the selected item

Hide or show the status bar in Finder windows

Add selected Finder item to the Dock (OS X Mavericks or later)

Open the Utilities folder

Show or hide the Dock. This often works even when you're not in the Finder

Add the selected item to the sidebar (OS X Mavericks or later)

Show or hide the tab bar when a single tab is open in the current Finder window

Show or hide a Finder tab

Create a new Smart Folder

Make an alias of the selected item

Open a new Finder window

Open the Help menu

Eject the selected disk or volume

Insert a new line after the insertion point

Move one character backward

Center the cursor or selection in the visible area

Center align

Left align

Decrease the size of the selected item

Press and hold for 5 seconds to force your Mac to turn off

Switch to the next most recently used window of the front app

Open preferences for the front app

Quit all apps, then shut down your Mac. If any open documents have unsaved changes, you'll be asked whether you want to save them

Boldface the selected text, or turn boldfacing on or off

Copy the selected item to the Clipboard. This also works for files in the Finder

Paste the contents of the Clipboard into the current document or app. This also works for files in the Finder

Use Quick Look to preview the selected item

Open an new document or window

Open the selected item, or open a dialog to select a file to open

Print the current document

Select All items

Find items in a document or open a Find window

Find Again: Find the next occurrence of the item previously found. To find the previous occurrence, press Command + Shift + G

Show or hide the Fonts window

Select the Desktop folder from within an Open dialog or Save dialog

Arrow Scroll to the end of a document

Move the insertion point to the beginning of the document

Move the insertion point to the end of the document

Delete the text between the insertion point and the end of the line or paragraph

Select Delete or Don't Save in a dialog that contains a Delete or Don't Save button

Scroll up one page

Delete the character to the left of the insertion point. Or use Delete

Select the text between the insertion point and the beginning of the document