Copy-and-paste-for-files

You can select files to copy with the keyboard. If I hold down a control and hit a, I will get everything in that folder. Maybe I don’t want all of these though.

Move-vs-copy

When you drag files from one folder to another, and those folders are on the same hard drive or thumb drive, just dragging them, actually moves the files from the source to the destination.

Undo-file-copy

If you ever had this happen, you go to drag some files from one folder to another, and instead of putting them on the folder you wanted, you accidentally dropped them somewhere else.