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Do I have to install it?
This program comes with any windows operating system, so no installation is required.
How to access the program
Pull up the start menu and start typing snipping, this will search through the programs and documents containing the word 'snipping'. The program will be retrieved as a best match.
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How do I markup the image using this tool?
Once the image has been snipped and is displayed in the preview window of the snipping tool, select the pen option or the highlighter option and start marking up the preview image.