title: relu as a parameter in Dense() ( or any other layer) vs ReLu as a layer in Keras
body: <p>I was just wondering if there is any significant difference between the use and speciality of</p>
  
  <pre><code>Dense(activation='relu')
  
  </code></pre>
  
  <p>and</p>
  
  <pre><code>keras.layers.ReLu
  
  </code></pre>
  
  <p>How and where the later one can be used? My best guess is in Functional API usecase but I don't know how.</p>