If for some reason your Android powered smartphone does not perform as good as it used to, or you want to sell it I suggest you to bring it to its original factory state.
You have more people using one computer and you don't want them to be able to shut it down using a shutdown button on Windows logon screen, this is how you remove it.
If you want you can turn any Microsoft PowerPoint presentation into a video so you can play the presentation on a computer that doesn't have Microsoft Office installed.
