diff --git a/handbook/introduction.xml b/handbook/introduction.xml
index 291ed5d214..7de74673fb 100644
--- a/handbook/introduction.xml
+++ b/handbook/introduction.xml
@@ -196,9 +196,14 @@ $ runqemu qemuarm
 
         <para>
             To build for other machines see the <glossterm><link
-                    linkend='var-MACHINE'>MACHINE</link></glossterm> variable in build/conf/local.conf
-            which also contains other configuration information. The images/kernels built
-            by Poky are placed in the <filename class="directory">tmp/deploy/images</filename>
+                    linkend='var-MACHINE'>MACHINE</link></glossterm> variable in build/conf/local.conf.
+            This file contains other useful configuration information and the default version
+            has examples of common setup needs and is worth 
+            reading. To take advantage of multiple processor cores to speed up builds for example, set the 
+            <glossterm><link linkend='var-BB_NUMBER_THREADS'>BB_NUMBER_THREADS</link></glossterm>
+            and <glossterm><link linkend='var-PARALLEL_MAKE'>PARALLEL_MAKE</link></glossterm> variables.
+
+            The images/kernels built by Poky are placed in the <filename class="directory">tmp/deploy/images</filename>
             directory.
         </para>
 
diff --git a/handbook/ref-variables.xml b/handbook/ref-variables.xml
index a3590e1072..4beb0cf35f 100644
--- a/handbook/ref-variables.xml
+++ b/handbook/ref-variables.xml
@@ -66,7 +66,7 @@
 
         <glossentry id='var-BB_NUMBER_THREADS'><glossterm>BB_NUMBER_THREADS</glossterm>
             <glossdef>
-                <para>Number of BitBake threads</para>
+                <para>The maximum number of tasks BitBake should run in parallel at any one time</para>
             </glossdef>
         </glossentry>
 
@@ -483,6 +483,14 @@
             </glossdef>
         </glossentry>
 
+        <glossentry id='var-PARALLEL_MAKE'><glossterm>PARALLEL_MAKE</glossterm>
+            <glossdef>
+                <para>Extra options that are passed to the make command during the 
+                    compile tasks. This is usually of the form '-j 4' where the number
+                    represents the maximum number of parallel threads make can run.</para>
+            </glossdef>
+        </glossentry>
+
         <glossentry id='var-PN'><glossterm>PN</glossterm>
             <glossdef>
                 <para>Name of package.