--- /dev/null
+``block``
+=========
+
+Blocks are used for inheritance and act as placeholders and replacements at
+the same time. They are documented in detail in the documentation for the
+:doc:`extends<../tags/extends>` tag.
+
+Block names should consist of alphanumeric characters, and underscores. Dashes
+are not permitted.
+
+.. seealso:: :doc:`block<../functions/block>`, :doc:`parent<../functions/parent>`, :doc:`use<../tags/use>`, :doc:`extends<../tags/extends>`