Emily has used this file format many times, as it is suitable for photographs, and highly compressed, which makes it a good idea when file storage is at a premium. what is this format?

JPEG There are a lot of different file compression formats that are usable for images, but the most likely one Emily is using is JPEG. The amount of compression you can get from JPEG is configurable as an input parameter where you can get more compression by losing more fine detail. At moderate levels of loss, you can get extremely high compression ratios. One of the major problems is that JPEG does not do well when you expand a compressed image, edit it, then compress the edited result. Because of this, for picture editing purposes, a lossless compression format is recommended for original images that may be edited in the future.