Windows 10 – Snipping Tool
To take a screenshot in Windows 10, search in the start menu for “Snipping Tool” and open it.
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The easiest way to use the the tool is to pick the Rectangular snip mode and then click “new” to draw a rectangle. Everything within the rectangle will be put into an image that you can then copy and paste or save as a file to your computer.
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Mac
For iMacs and Macbooks, press Shift-Command-4 to take a screenshot. You can read more about taking screenshots on Mac at: https://support.apple.com/en-us/HT201361