diff --git a/docs/manifest-format.txt b/docs/manifest-format.txt
index 338e021..f499868 100644
--- a/docs/manifest-format.txt
+++ b/docs/manifest-format.txt
@@ -184,11 +184,12 @@
 
 Attribute `groups`: List of groups to which this project belongs,
 whitespace or comma separated.  All projects belong to the group
-"default", and each project automatically belongs to a group of
-it's name:`name` and path:`path`.  E.g. for
+"all", and each project automatically belongs to a group of
+its name:`name` and path:`path`.  E.g. for
 <project name="monkeys" path="barrel-of"/>, that project
 definition is implicitly in the following manifest groups:
-default, name:monkeys, and path:barrel-of.
+default, name:monkeys, and path:barrel-of.  If you place a project in the
+group "notdefault", it will not be automatically downloaded by repo.
 
 Element annotation
 ------------------