Pages section vs. pages field:
Pages section
- list + create pages
- only pages from one parent
- filterable by template + status only
Pages field
- select one or more pages from a given set of pages
- IDs of the selected pages are stored in the content file (useful to create references, e.g related pages)
- can query pages from different parents via query option (does not have a parent property)
- currently no option to create new pages (but on the roadmap)
There’s also a files section and a files field, the distinction is somewhat similar (but files field already has upload functionality)