title: What is the difference between CloudBlob subclasses?
body: <p>Looks like <a href="https://msdn.microsoft.com/en-us/library/azure/microsoft.windowsazure.storage.blob.cloudblob.aspx" rel="noreferrer">CloudBlob</a> has 3 subclasses you can use to get data in and out of Azure Storage.  Here's the (very sparse) documentation:</p>
  
  <ul>
  <li>Microsoft.WindowsAzure.Storage.Blob.<a href="https://msdn.microsoft.com/en-us/library/azure/microsoft.windowsazure.storage.blob.cloudblockblob.aspx" rel="noreferrer">CloudBlockBlob</a>
  
  <ul>
  <li><blockquote>
    <p>Represents a blob that is uploaded as a set of blocks.</p>
  </blockquote></li>
  </ul></li>
  <li>Microsoft.WindowsAzure.Storage.Blob.<a href="https://msdn.microsoft.com/en-us/library/azure/microsoft.windowsazure.storage.blob.cloudappendblob.aspx" rel="noreferrer">CloudAppendBlob</a>:
  
  <ul>
  <li><blockquote>
    <p>Represents an append blob, a type of blob where blocks of data are always committed to the end of the blob.</p>
  </blockquote></li>
  </ul></li>
  <li>Microsoft.WindowsAzure.Storage.Blob.<a href="https://msdn.microsoft.com/en-us/library/azure/microsoft.windowsazure.storage.blob.cloudpageblob.aspx" rel="noreferrer">CloudPageBlob</a>
  
  <ul>
  <li><blockquote>
    <p>Represents a Microsoft Azure page blob.</p>
  </blockquote></li>
  </ul></li>
  </ul>
  
  <p>I've been using <code>CloudBlockBlob</code> to upload/download pdfs and images, and everything seems to be working.  I can't seem to find a page that explains what these classes do.</p>
  
  <p>Under what circumstances should I use <code>CloudAppendBlob</code> and <code>CloudPageBlob</code>?</p>