Often times, people find themselves needed to get a screen shot of something that's on their computer. Students, employees, or end-users may need to show others what was on their screen as part of a report, demonstration, or example of something that went wrong (in the case of end-users who need to email their tech support an example of a problem they're experiencing). You can do this easily, with a few key strokes.
On the screen you'd like to save, hold down the "Shift" key on your keyboard, and then press the "Print Screen" key.
Open up Microsoft Paint (or similar program).
In Microsoft Paint, click "Edit" on the top tool bar, and choose "Paste" from the drop down menu. In MS Paint, you can now edit your screen shot as needed. You may want to "highlight" certain areas, or use arrows to indicate to your reader what section of the screen you're referring to.
Click on "File," on the top navigation bar, then choose "Save as" from the drop down menu.
Microsoft Paint will default to wanting to save the file as a bitmap, but by clicking on "Save as type" below the file name, you can choose "jpg."
Use your saved screen shot as you would use any other jpg file.