diff --git a/ChangeLog b/ChangeLog
index 4ed1a15718cfe97bc069935007aab7c11bd09962..23c48fbacb569d4738c74386886a873940fd43bb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2009-05-31  Per Cederqvist  <ceder@lysator.liu.se>
 
+	Document the file types and file object types that lyskomd uses.
+	* doc/lyskomd.texi (File Object Types): New node.
+	(File Types): New node.
+	
 	Fix menus in documentation.
 	* doc/lyskomd.texi (Hacking): Fill in descriptions in the menu.
 
diff --git a/doc/lyskomd.texi b/doc/lyskomd.texi
index e5be6f086f8e1975a52f197053ab22a2e4598ba3..c4d7866d131f745b5dbf09ca0b12747e8dd7418c 100644
--- a/doc/lyskomd.texi
+++ b/doc/lyskomd.texi
@@ -1762,6 +1762,8 @@ information on how to restore the database.
 
 @menu
 * The Database::                How metadata is stored.
+* File Object Types::           Index of type codes in files.
+* File Types::                  Index of magic cookies in files.
 * Adding Configuration Parameters::  How to add configuration options.
 * Adding Asynchronous Messages::  Adding protocol A messages.
 * Adding a New Protocol Request::  Adding protocol A calls.
@@ -2007,6 +2009,60 @@ starting lyskomd again.  You must do this periodically (as explained
 in @pxref{Administration}), or the text file will keep growing
 forever.
 
+@node File Object Types
+@section File Object Types
+
+Here is a summary of all the object types used in various database
+files.  The table is sorted alphabetically.  While most object types
+are single-character types, there are a few exceptions.
+
+@table @samp
+
+@item #C
+The number of conferences in the database file.
+@xref{lyskomd Database Specification}.
+
+@item #T
+The number of texts in the database file.
+@xref{lyskomd Database Specification}.
+
+@item C
+A conference.
+@xref{lyskomd Database Specification}.
+
+@item I
+An info structure.
+@xref{lyskomd Database Specification}.
+@xref{(protocol-a)Server Information, Info}, for the datafile
+version.
+
+@item P
+A person.
+@xref{lyskomd Database Specification}.
+
+@item T
+A text status.
+@xref{lyskomd Database Specification}.
+
+@end table
+
+@node File Types
+@section File Types
+
+Here is a summary of the magic markers used in file headers by
+lyskomd.  The table is sorted alphabetically.
+
+@table @samp
+@item CLEAN
+A complete database file.
+@xref{lyskomd Database Specification}.
+
+@item DIRTY
+An incomplete database file.
+@xref{lyskomd Database Specification}.
+
+@end table
+
 @node Adding Configuration Parameters
 @section Adding Configuration Parameters