1.Control + Option + Command + Eject
Use the keyboard combination of Control + Option + Command + Eject to instantly shut down your Mac. This is a great time saver because it bypasses the shut down counter that you get when using Apple menu > Shut Down. As an alternative, you can also press Option + Command + Eject to sleep your Mac.
2. Command + Shift + A/U/D
These keyboard shortcuts are used to navigate around the Finder. To open the Applications folder on your Mac, press Command + Shift + A in an opened Finder window; press Command + Shift + U to open the Utilities folder; and, press Command + Shift + D to open your Desktop folder in the Finder. These keyboard shortcuts can also be used when in an opened save dialog to navigate to these folders.
3. Shift + Command + I
When used inside of Safari, this keyboard shortcut (Shift + Command + I) will automatically generate a new email message inside of and paste the link of the web page you were browsing in the body text. This shortcut is great for quickly sharing a website address with a friend via email.
4. Control + D
To the bane of many Windows to Mac switchers, the Mac’s “Delete” key doesn’t actually function as the delete key as it does in Windows. The “Delete” key on the Mac instead functions as a backspace. Instead use Command + D in any text area on your Mac to delete from the front of the cursor.
5. Control + Option + Command + 8
6. Control + Command + D
When writing, we often need to quickly look up the meaning of a word; however, it can be a pain to open and type in the word we want to look up. Instead, we prefer this nice way to quickly look up a word. With your mouse cursor over top of the word you’d like to look up, press Control + Command + D. A dialog will then pop up with the word defined by the built-in Mac OS X dictionary. While holding down the keyboard combination, you can mouse around to different words in the document.
7. Command + Shift + 4 + Space bar
Screen shot of only required window. To grab just a one-window screenshot, press Command + Shift + 4, then when the cross hairs appear, press the space bar. The cross hairs will change to a picture of a camera that can be placed over top of the window to be captured and clicked. The resulting window-only screenshot will appear on your Desktop.
8. Option + Command + M
When working on a large task, you lose track of just how many windows you’ve opened on your Mac. To minimize all of your opened windows and clean-up your screen, just press Option + Command + M to have all of the windows minimized to the Dock.
9. Option + Shift + Command + Esc
Applications can sometimes crash. When this happens, you can press and hold Option + Shift + Command + Esc to instantly Force Quit the application, and bypassing the Force Quit app.
10. Command + `
Exposé and Command + Shift is a great way to cycle through all of the different applications and windows currently opened on your Mac, but what if you only want to cycle through the current application’s opened windows? In that case, use Command + ` This combination will cycle through all of the opened windows in the currently active application.