Manager shows all images attached to the project.
Unique images - helps a little to modify the image, thus making them unique in the eyes of search engines.
Due to this function you can easily upload all the pictures from the project to the third-party file hosting (or vice versa, download external links to the local computer).
This tool allows you to insert small pictures with reference to the original image. This increases the attractiveness of the article for the search engines, and users.
Local images - automatic image insertion to posts.