Wipes all open space on your hard drive, so no previously deleted files can be recovered. When you delete files from your pc, they can be recovered from your hard drive. Many files that you thought were long gone, may be recovered, whether they are important documents, pictures, tax documents, videos, photos, and more. If you are selling, donating, or giving away your pc, then this program is a must. Running this program will fill up and overlay your empty disk space with random characters, and any attempts at file recovery will be useless. This will not actually fill up any hard drive space, your free space will remain the same when this has completed, but all previously deleted files will not be able to be recovered. (Runs on all Windows systems.)