:.obj is a

The .is instance of property is used to state that a given object (=wiki page) is perceived as an instance of the specified class. Note that there is an article called "Class Xyz" for every class "Xyz" which contains meta data about that class. Ideally a separate namespace could be used for class definitions but due to technical problems with the current version of Semantic Mediawiki we use ordinary pages in the main namespace and add the "Class " prefix.

The Template class is used to assign this property. So, in an article called Peter you might write: {{class|Person}}.

The class of an object can be seen as its "fundamental category". Assigning an object to a class gives you access to meta data about that class. This meta data defines which properties can be used to describe instances of that class. It also describes which properties point to other class instances (of the same class or of different classes). It assigns a color scheme to a class etc.

Trying to assign properties which are not defined in the meta model will cause a warning.

This property is assigned by .prop assigned by::Template:.obj is a