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.
As from November 11th Google will launch a so called Shared Endorsements for products or services which will allow them to use your picture when displaying ads to your friends.
If you don't want others to use your photos and images without your permission, you can create a so called custom watermark with your name or any other text you want.
Let me demonstrate you how easy it is to add an old school looking countdown timer or a so called universal counting leader to you video projects in Adobe Premiere CC.