Photos To Disk helps you retrieve your original photos and videos (including photos in RAW file format) from your Photo Library in just a few easy steps. Metadata (title, description, keywords, and location) can be embedded into JPEG, PNG, TIFF, and PSD image files or stored in XMP sidecar files for other image file formats. Media files can be renamed after the titles that you have eventually defined in Photos. You can also prefix file names with media dates or media dates/hours.
The export feature is typically used to retrieve a large number of photos and videos for use in other photo-editing software, or for transferring them to third parties. The backup feature is used to keep a well-structured copy of your entire Photo Library in a non-proprietary format. Once you have defined your Backup Folder, updating your backup with your most recent photos and videos simply requires a click on one of the "Backup" buttons.