Command-Shift-3 takes a picture of the entire screen. Command-Shift-4 takes a picture of whatever you draw a box around. There are other options too!
How to take a picture of the screen (screenshot) on a Mac
How to be faster with Safari, Chrome, and Firefox on a Mac
Most people work harder than they have to where web browsing is concerned. Here are two time-saving tips to help you in Safari, Chrome, and Firefox.
Essential Mac Keyboard Shortcuts: Command-1, -2, -3, and -4
Switch between the Finder's icon and list views with simple keyboard shortcuts. What could be easier than Command-1 and Command-2?
How to access your Mac’s Library folder
Apple hides your Library folder because they don't want you accidentally messing it up. When you have to get into it, use the Option key and the Go menu.
Close every window of a Mac app, all at once
Command-W does what a click on the red button does. Command-Option-W does what an Option-click on the red button does-- close all windows for that app.
Essential Mac Keyboard Shortcuts: go to the Desktop with ⌘-Shift-D
Quickly go to the Desktop folder with Command-Shift-D. It's fast, and it works both in Finder windows and in Open... and Save... dialog boxes.
Use the ⌘-Spacebar shortcut to bring up Spotlight on a Mac
The Mac's Spotlight system can help you find just about anything on your Mac. Make it easier to use by triggering it with a shortcut.
Print in a hurry on a Mac: ⌘-P, then Enter
Mac users: save a few seconds every time you go to print! The seconds you save add up. Maybe enough to learn to play the piano.
How to Type the Apple Logo
Every Mac users should know how to type the Apple logo. Turns out it's built into almost every font and it's easy as pie to do.
Use Control-Eject to bring up Restart/Sleep/Shutdown dialog on a Mac
Bring up the Mac's Restart/Sleep/Shutdown dialog box, as if you'd pressed the power button. Much more conenient to do it this way.