Delete mode identifies the method used for deleting files. There are three modes available: normal, recycle and wipe and delete.
The normal delete mode simply marks the file as deleted (same as a DOS delete or a Windows delete plus a purge from the recycle bin). Marking a file as deleted simply removes the file pointer, but leaves the data on the disk. Since the data space is freed, the old data may eventually be overwritten by other files, but will remain on the disk until more data is stored.
The recycle mode moves the deleted files to the recycle bin.
The wipe and delete mode actually overwrites all data in the file prior to freeing the space on the disk, and is therefore useful for deleting sensitive or confidential data.
Normal: Use the normal mode (because it is much faster) if you don't care about the possibility of others finding your data.
Recycle: Delete the files but use the Windows recycle bin (move the files to the recycle bin).
Wipe and delete: Use the wipe and delete mode if you want to ensure that the deleted data is not recoverable due to data sensitivity issues.
Access: "File", "Delete Mode" (toggles "normal" and "wipe and delete")