title: what is the difference between the java.lang.Math class and the java.Math class
body: <p>I am trying to figure out which 'Library'  the BigDecimal Class resides in.  When I read the referencing information it says this:</p>
  
  <pre><code>java.lang.Object
       java.lang.Number
            java.math.BigDecimal
  </code></pre>
  
  <p>which I don't totally understand.  I am familiar with the java.lang.Math class.  I assume this is entirely different - so here are my sub-questions:</p>
  
  <p>First - am I correct in saying that the java Math class resides in the java.lang library</p>
  
  <p>second -  Does java.math.BigDecimal extend java.lang.Number, and if not, how are they related?</p>
  
  <p>Third - is there a relationship to java.lang.math and java.math?</p>