Most devices let you delete data from them; For instance, you can drag a file to the Trash icon, or press delete in a photo album. But deletion does not always mean that the original data is gone. Undelete programs are applications that can be used by the device's owner, or others with access to the device, to restore some data. Undelete programs are useful for those who accidentally delete their own data, and to those whose data might have been sabotaged, such as a photographer who has been compelled to remove images from their camera. However, those same programs can be a threat to anyone who wants to permanently erase confidential data. See How to Delete Your Data Securely for advice on wiping data, and how undelete programs work on modern devices.