Screen captures have many uses, including Web graphics, images in Powerpoint presentations, or how-to screens for training documents. Mac OSX users can create a screen capture of any size by simply holding down Shift + Command + 4. Once selected, crosshairs appear with numbers that represent the X and Y axis. Click and drag the mouse to cover the portion of the screen you want to capture and then let go. The image will be waiting for you on the desktop as a .png file.

Additionally, the window camera will appear if you hold down Shift + Command + 4 and then tap the spacebar. Clicking on the mouse will then create a pre-cropped screen shot of only the active window.