title: Creating Numpy structured array
body: <p>While brushing up my numpy skills, I've encounter the structured array.</p>
  <pre class="lang-py prettyprint-override"><code>&gt;&gt;&gt; import numpy as np
  &gt;&gt;&gt; person_data_def = [('name', 'S6'), ('height', 'f8'), ('weight', 'f8'), ('age', 'i8')]
  &gt;&gt;&gt; person_data_def
  [('name', 'S6'), ('height', 'f8'), ('weight', 'f8'), ('age', 'i8')]
  </code></pre>
  <p>What are <code>S6</code>, <code>f8</code> and <code>i8</code> in this context?</p>