More Identifier documentation

1 files changed, 10 insertions, 0 deletions

diff --git a/src/Hakyll/Core/Identifier.hs b/src/Hakyll/Core/Identifier.hs
index ea03e8c..16403e6 100644
--- a/src/Hakyll/Core/Identifier.hs
+++ b/src/Hakyll/Core/Identifier.hs
@@ -10,6 +10,16 @@
 --
 -- * @error/404@
 --
+-- The most important difference between an 'Identifier' and a file path is that
+-- the identifier for an item is not necesserily the file path.
+--
+-- For example, we could have an @index@ identifier, generated by Hakyll. The
+-- actual file path would be @index.html@, but we identify it using @index@.
+--
+-- @posts/foo.markdown@ could be an identifier of an item that is rendered to
+-- @posts/foo.html@. In this case, the identifier is the name of the source
+-- file of the page.
+--
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 module Hakyll.Core.Identifier
     ( Identifier (..)