: Schema.org terms can act both as properties or types? I installed an RDF module on my Drupal 8 site and it seems that I can pick the exact options from the exact same list for both Content

@Ann8826881

Your assumption is correct. Schema.org types (aka. classes) are not supposed to be used as properties, and vice-versa. (Technically they could be used for anything, but it wouldn’t make sense to do this.)

But the RDF UI module is doing it correctly:


When editing a content type, you can select (under "Schema.org Mappings") a type:


Specify the type you want to associated to this content type e.g. Article, Blog, etc.


The autocomplete list correctly lists/suggests types, i.e., terms that start with an uppercase letter (like Thing).
When mapping a field (under "Manage fields" → "RDF Mappings"), you can select a property.

The autocomplete list correctly lists/suggests properties, i.e., terms that start with a lowercase letter (like name).


If you have a content type "Team member", you could map it to the Schema.org type Person, and the field "Title" could be mapped to the Schema.org property name.

Background

Note that it’s just a convention (followed by Schema.org and many other vocabularies) to start types with uppercase letters, and properties with lowercase letters. A vocabulary could as well use x8234 for a type and x8238 for a property.

If something is supposed to be a type or a property should ideally become clear in the vocabulary’s documentation, but the canonical definition can be found in the vocabulary’s RDF.

In case of Schema.org (canonical definition in RDFa), you can see that name is of type rdf:Property:




<div typeof="rdf:Property" resource="http://schema.org/name">
<!-- … -->
</div>



and Person is of type rdfs:Class:


<div typeof="rdfs:Class" resource="http://schema.org/Person">
<!-- … -->
</div>

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