EXIF stands for Exchangeable Image File Format
In practical terms, EXIF is a set of metadata fields stored inside many image files. Those fields can describe the device used to capture the picture, the time it was taken, camera settings, orientation, and sometimes the location where the photo was created.
This information can be useful when photographers organize a library or when editing software needs to understand the original image. It can also be unnecessary or risky when the image is about to be sent to a client, posted publicly, or shared on a marketplace.