If you are tired and annoyed by the app requests and notifications your friends keep sending on Facebook, this is how you get rid of them without having to unfriend your friends.
Knowing how to select parts of your Gimp documents with the help of Quick Mask might be one of the first things you should learn when starting with Gimp. Let me introduce you to the basics of Quick Mask.
You don't need Photoshop or some other advanced piece of software to resize a large number of images at once. You can use Microsoft Office Picture Manager which is part of the Office suite.