How To: FREE Screen Capture FOR MAC and WINDOWS
All versions of Mac OS and Windows allow you to take a picture of your screen. Once you have the screen capture you can get fancy by editing it using a built in graphics tools or just copy and paste the entire graphic into a document to share with your friends, students or colleagues. Great info for making Power Point Presentations or using to print hand outs to show exaclty what you want them to see on their screen.
Mac Screen Capture
To snap the whole screen, but you can use Command-Shift-4 to instead get a crosshair pointer that you can use to select just a portion of the screen. If the Caps Lock is down when you do this, the cursor instead turns to a bullseye. If you use this bullseye to click a window, it takes a picture of just that window. In summary:
Command-Shift-3 ................ entire screen
Command-Shift-4 ................ crosshairs -- selected area
Command-Shift-4 + Caps Lock .... bullseye -- selected window
Windows Screen Capture
Pressing the PrintScreen key will do a screen capture of the full screen to the clipboard. You can use Paint (which comes with Windows) to edit the image (simply start a new document and PASTE from the clipboard). If you press Alt-PrintScreen then only the current window will be captured to the clipboard. Again, you can use paint to edit/crop the image and save to a file.
Screen Capture Software
If you need to get more sophisticated you may need to get free screen capture software.