The more you know. I also want to add that if it is an image from the internet, you don't need to save it to your device, with right click → copy image (Ctrl + c might copy the file instead) is enough. But for an image already stored in your device, you might need to open it in an editor (one as simple as MS Paint is enough) then select everything and copy. The importan thing is that the raw bitmap data is in the clipboard instead of file itself.
Also, animated gif are an exception, if you do that with a gif, you're only copy a single frame of the animation, so you need to copy the file in this case.