title: Difference between nothing and system.DBNull
body: <p>I am working in VB.NET and I am wondering about the difference between <code>Nothing</code> and <code>System.DBNull</code>.</p>
  
  <p>When I fire save query at that time I am giving value from grid at runtime like as follow:</p>
  
  <pre><code>gvMain.Rows(j).Cells("Brand").Value.ToString()
  </code></pre>
  
  <p>But it shows me error when it has value of <code>Nothing</code> and it works perfectlly when it has value of <code>System.DBnull</code>.</p>
  
  <p>What to do in this case?<br>
  Thanks in advance</p>