title: VB.NET What is Sender used for?
body: <p>I'm confused as to the purpose of the <code>sender</code> parameter in Winform controls, for example:</p>
  
  <pre><code>Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
  
  End Sub
  </code></pre>
  
  <p>I understand i can verify what <code>sender</code> holds by doing something as so:</p>
  
  <pre><code>If TypeOf sender Is Label Then
   'Execute some code...
  End If
  </code></pre>
  
  <p>But is there a good reason that sender is included in every single control when it generates the sub-routine for me? In other words, i double click on a Form and i get the <code>Private Sub form_load (sender....)</code> <em>and</em> <code>e As System.EventArg</code>s.</p>
  
  <p><strong>What are some common usage of these two parameters? Are they always required?</strong></p>
  
  <p>Thank you,</p>
  
  <p>Dayan D.</p>