Copying Files and Folders
But you can also copy a file or folder by holding down the Ctrl key before you start a drag-and-drop operation. When you do this, the mouse cursor will change to represent a hand dragging something, with a plus sign at its bottom right, as shown in Figure 6-4. Keep the Ctrl key held down until you release the mouse button, or the operation will return to being a simple move, rather than a copy operation.

Figure 6-4. Copying a file using the mouse
Warning
Copying a folder results in all its subfolders also being copied; if these folders contain very large files, this could take a while and use a lot of disk space.
Copying with External Media
There is no need to hold down the Ctrl key when copying files from one media device to another—whether from a CD-ROM to your hard disk, or vice versa, or between a DVD-ROM and a USB thumb drive, and so on.
Just drag and drop the files you want to copy, and Ubuntu will know that this is a copy operation, so your original files will not be deleted. However, they will remain highlighted so that you can more easily delete them should you wish (if the media is writeable), without having to select them again—which I’ll talk about next.