Exploring EXIF ⇥ hturan.com
According to iOS’ Photos application, I’ve taken 73,281 photos over the past 14 years of owning an iPhone.
Each one of those images doesn’t just contain the photo you see as you scroll through the Photos app — it contains a wealth of information stored encoded directly into the image file itself. It details useful metadata such as where the photo was taken (so that you can view your photos on a map at a later date), the time and date the image was taken at, which lens and zoom levels were used, the exposure, ISO, and aperture, amongst many others.
This is an excellent exploration of EXIF data and how it can be used, including in some pretty surprising and privacy-hostile ways. I cannot recommend enough that you play around with ExifTool, just to see what is known about different files — and not just photos: while it may be named for a photographic term, ExifTool can surface all kinds of metadata.