We exclusively organize digital objects (e.g. PDF files).

We do not organize information on physical objects (e.g. notes

on a book) or digital objects (e.g. metadata).

We exclusively organise physical objects (e.g. books on shelves).

We organise physical objects (e.g. books on shelves), information about physical objects (e.g. notes in a book), digital objects (e.g. websites) and information about digital objects (e.g. links).