Added pydoc section

Author: kuyan

docs/intro/documentation.rst

@@ -20,3 +20,21 @@ both popular and exotic.
     `Read the Docs <https://readthedocs.org/>`_
 
 
+pydoc
+-----
+
+:program:`pydoc` is a utlity that is installed when you install Python.
+It allows you to quickly retrieve and search for documentation from your
+shell. For example, if you needed a quick refresher on the
+:mod:`time` module, pulling up documentation would be as simple as
+
+    .. code-block:: bash
+
+       $ pydoc time
+
+The above command is essentially equivalent to opening the Python REPL
+and running
+
+    .. code-block:: python
+
+       >>> help(time)