title: how hibernate can work without JPA specification
body: <p>I was working on project which did not have <code>JPA</code>, however it uses <code>Hibernate</code>
  could anyone please explain how? </p>
  
  <p>The project's <code>pom.xml</code>:</p>
  
  <pre><code>   &lt;dependency&gt;
         &lt;groupId&gt;org.hibernate&lt;/groupId&gt;
         &lt;artifactId&gt;hibernate-core&lt;/artifactId&gt;
         &lt;version&gt;${hibernate.version}&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.hibernate&lt;/groupId&gt;
          &lt;artifactId&gt;hibernate-entitymanager&lt;/artifactId&gt;
          &lt;version&gt;${hibernate.version}&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.hibernate&lt;/groupId&gt;
          &lt;artifactId&gt;hibernate-validator&lt;/artifactId&gt;
          &lt;version&gt;5.1.3.Final&lt;/version&gt;
      &lt;/dependency&gt;
  </code></pre>