diff --git a/documentation/ref-manual/ref-classes.xml b/documentation/ref-manual/ref-classes.xml
index 8a52821aaa..3fa50155a8 100644
--- a/documentation/ref-manual/ref-classes.xml
+++ b/documentation/ref-manual/ref-classes.xml
@@ -211,6 +211,29 @@
     </para>
 </section>
 
+<section id='ref-classes-bin-package.bbclass'>
+    <title><filename>bin_package.bbclass</filename></title>
+
+    <para>
+        The binary package (<filename>bin_package</filename>) class is a
+        helper class for recipes that extract the contents of a binary package
+        (e.g. an RPM) and install those contents rather than building the
+        binary from source.
+        The binary package is extracted and new packages in the configured
+        output package format are created.
+        <note>
+            For RPMs and other packages that do not contain a subdirectory,
+            you should specify a "subdir" parameter.
+            Here is an example where <filename>${BP}</filename> matches the
+            subdirectory expected by the default value of
+            <link linkend='var-S'><filename>S</filename></link>:
+            <literallayout class='monospaced'>
+     SRC_URI = "http://example.com/downloads/somepackage.rpm;subdir=${BP}"
+            </literallayout>
+        </note>
+    </para>
+</section>
+
 <section id='ref-classes-debian'>
     <title>Debian Renaming - <filename>debian.bbclass</filename></title>