To see the metadata you have to consider the prefix statements that must be 
made before you can use the triples in your example/

@prefix rdf: http://www.w3.org/1999/02/22-rdf-syntax-ns#

click on the hyperlink to follow it.

Using this prefix statement adds metadata essential to understanding the triple:
Student rdf:type Person

rdf:type means:
rdf:type a rdf:Property ;
        rdfs:isDefinedBy <http://www.w3.org/1999/02/22-rdf-syntax-ns#> ;
        rdfs:label "type" ;
        rdfs:comment "The subject is an instance of a class." ;
        rdfs:range rdfs:Class ;
        rdfs:domain rdfs:Resource .

The object “Person” in the triple may also have metadata associated with it.
If the prefix:

@prefix foaf: http://xmlns.com/foaf/0.1/

is used the metadata associated with foaf:Person is

<rdfs:Class rdf:about="http://xmlns.com/foaf/0.1/Person"; rdfs:label="Person" 
rdfs:comment="A person." vs:term_status="stable"><rdf:type 
rdf:resource="http://www.w3.org/2002/07/owl#Class"/><owl:equivalentClass 
rdf:resource="http://schema.org/Person"/><owl:equivalentClass 
rdf:resource="http://www.w3.org/2000/10/swap/pim/contact#Person"/><!--    
<rdfs:subClassOf><owl:Class 
rdf:about="http://xmlns.com/wordnet/1.6/Person"/></rdfs:subClassOf> 
--><rdfs:subClassOf><owl:Class 
rdf:about="http://xmlns.com/foaf/0.1/Agent"/></rdfs:subClassOf><!--    
<rdfs:subClassOf><owl:Class 
rdf:about="http://xmlns.com/wordnet/1.6/Agent"/></rdfs:subClassOf> 
--><rdfs:subClassOf><owl:Class 
rdf:about="http://www.w3.org/2003/01/geo/wgs84_pos#SpatialThing"; 
rdfs:label="Spatial Thing"/></rdfs:subClassOf><!-- aside: 
        are spatial things always spatially located? 
        Person includes imaginary people... discuss... 
--><rdfs:isDefinedBy rdf:resource="http://xmlns.com/foaf/0.1/"/><!--    
<owl:disjointWith rdf:resource="http://xmlns.com/foaf/0.1/Document"/> this was 
a mistake; tattoo'd people, for example. 
--><owl:disjointWith 
rdf:resource="http://xmlns.com/foaf/0.1/Organization"/><owl:disjointWith 
rdf:resource="http://xmlns.com/foaf/0.1/Project"/></rdfs:Class>


So you can see even a simple statement like 

Student rdf:type foaf:Person

contains a huge amount of metadata that can be located and used by a machine!




On 7/6/17, 1:07 am, "tina sani" <[email protected]> wrote:

    For example, there is an rdf document about a student.
    
    Student rdf:type Person. Student hasName name.  Student hasAdress adress
    
    Student study Course.
    
    Where is the meta data here. How machines understand this data.
    
 



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