diff --git a/docs/_static/img/concepts.png b/docs/_static/img/concepts.png
index fd9fd816..3bf55b5b 100644
Binary files a/docs/_static/img/concepts.png and b/docs/_static/img/concepts.png differ
diff --git a/docs/framework/basic_concepts.rst b/docs/framework/basic_concepts.rst
index 1ba4171b..74db7a8a 100644
--- a/docs/framework/basic_concepts.rst
+++ b/docs/framework/basic_concepts.rst
@@ -18,13 +18,14 @@ The most important concepts in the library are `Unit`, `Dimension`,
     [exponent<Dimension, Num, Den>]<-[derived_dimension<Child, Unit, Exponent...>]
     ]
 
-    [<abstract>Quantity|
-    [quantity<Dimension, Unit, Rep>]
+    [<abstract>QuantityPoint|
+    [quantity_point<Dimension, Unit, Rep>]
     ]
 
     [<abstract>Unit]<-[Dimension]
     [Dimension]<-[Quantity]
     [Unit]<-[Quantity]
+    [Quantity]<-[QuantityPoint]
 
 `Unit` is a basic building block of the library. Every dimension works with
 a concrete hierarchy of units. Such hierarchy defines a reference unit and