Are your deleted files, actually deleted..?

• Little background: Your computer knows where files are physically located on your hard disk by looking up their location in a sort of table of contents.

•  So when you empty your recycling bin, the files are still physically present on your hard disk, but your operating system (OS; e.g. Windows, Linux, etc.) erases the record of the file's existence from the table of contents.

•  The physical location on your hard disk that your deleted file used to take up (and still is taking up until the data is over-written by another file) now looks like free space to your OS and other files can use that space.

•  Extra info: There are programs that do a sort of reverse process in which they first go to the physical hard disk and read the files. Then they record the files' locations in the table of contents so that the files "exist" again and the OS knows of their "existence". This is what "data" recovery is; re-writing the table of contents if it is accidentally erased.