Just started using this program recently. Essentially it is a JPEG shrinking program that shrinks photos in such a way that there is no perceptible loss in image quality. As image sensors get bigger and bigger the size of JPG's has grown as well. I have a digital camera that takes 5-7MB photos with every shot. This program reduces the file size to approximately 2MB. I've applied to the photos I took in this year and saved about 2GB of storage space.