To capture something on your screen you use PrtSc.
If you use Alt+PrtSc it captures the top active window on your computer.
If you use Ctrl+PrtSc (control+print screen) it captures everything on your screen.
I use a simple program like MSPaint to paste my screen grabs in. So which ever you choose (Alt, or Ctrl), you open up MS Paint and click paste (or keyboard short cut Ctrl+V). You can then save the image on your computer. It's a great way to save confirmation orders, or other things you want to grab on the fly. (examples: recipes, an important email (Instead of sorting through all your emails to find it again))
You can use Photoshop, Corel, Pant Shop Pro, GIMP, or any other image editing software to post your screen grab in. MSPaint loads fast and is easy to paste and save. You can also quickly crop the image down to just the info you want to save....but that's another lesson.
