add some prose trying to explain Attribute and ObjectIdentifier
diff --git a/docs/x509.rst b/docs/x509.rst
index 19a62be..42b95a1 100644
--- a/docs/x509.rst
+++ b/docs/x509.rst
@@ -185,6 +185,8 @@
.. versionadded:: 0.8
+ An X.509 name consists of a list of Attribute objects.
+
.. attribute:: oid
:type: :class:`ObjectIdentifier`
@@ -201,6 +203,9 @@
.. versionadded:: 0.8
+ Object identifiers (frequently seen abbreviated as OID) identify the type
+ of a value (see: :class:`Attribute`).
+
.. attribute:: value
:type: :class:`str`