title: how scatter function work in python for plotting graph
body: <p>How does the scatter function work here? I would like to know what <code>c=Y</code> means and what is <code>X[:,0]</code> and <code>X[:,1]</code> in the following code.</p>
  
  <pre><code>#make_blob is data set
  
  X, Y = make_blobs(n_samples=500, centers=2, random_state=0, cluster_std=0.40) 
  plt.scatter(X[:, 0], X[:, 1], c=Y, s=50, cmap='spring')
  plt.show() 
  </code></pre>