title: What's mean 'fb' and 'b' in Jena rules //OWL, RDFS
body: <p><img src="https://i.stack.imgur.com/ZH6VE.jpg" alt="enter image description here"></p>
  
  <p>There is a Jena rules <br>
  I don't know prefix b and fb.
  What different things each OWL and RDFS files?</p>
  
  <p>PS.
  download URL is 
  <a href="https://jena.apache.org/download/index.cgi" rel="nofollow noreferrer">https://jena.apache.org/download/index.cgi</a> and click jena-2.11.1-source-release.zip (MD5, PGP)</p>
  
  <p>rules dir -> jena-core/src/main/resources/etc</p>