Print screen

A little feature of your computer (both Mac and PC) often overlooked is the ability to take a photo of what's on your screen, known variously as a screen shot, screen dump or screen capture. I use this quite regularly, usually to extract a pic from a Word document or a pdf file. Now I know that you can copy a photo from Word and paste it into an imaging program like Photoshop or Irfanview, but the result is often awful quality. A better alternative in that case is to zoom right in on the image - say around 500% - and take a screen shot, then paste that into Photoshop. If the photo extends beyond the borders of the screen, take shots of it in sections, and montage the sections. The same technique can be used to extract pics from a pdf document; although in theory Acrobat has a tool to grab pics, I find that sometimes the results are not good.
To print your screen, look for the "Print Screen" (or maybe Prnt Scrn") key, which is probably at the top right of your keyboard. You can paste the image straight into a Word document, but not an email; for that you have to save the pic to your hard drive. To save the pic, open your image editing program, make a new document (from the File menu), and then use the paste command. Crop as appropriate and save. If you paste into Photoshop, it automatically creates a new layer for the image, so you will have to merge the layers (Ctrl-E or Cmd-E)) in order to save as a jpg or tif image.
The PC Print Screen facility is very basic, and there are many screen capture programs which can do a better job. A free one I use is Gadwin Print Screen.