iPad Storage: "Media" vs "Photos"

I'm attempting to free up some storage on my iPad (MP2F2LL/A, 32GB, iOS 11.2.6).

When I got to Settings / General / iPad Storage, I have 8.36 GB in photos, but also a substantial amount of "Media" based on the blue bar that is part of the color-coded breakdown of your storage.

What counts as "Media"? I'm not seeing large file sizes anywhere else in the summary. My next biggest app after "Photos" is "Numbers" with 360 MB.

Thanks!