Includes quick aside on what a refspec is

Author: randomecho

branching/index.html

@@ -242,7 +242,8 @@ <h4>
 
     <p>Alternatively, you can run
     <code>git push remote-name --delete branchname</code>
-    which is a wrapper for the colon technique of deleting a remote branch.
+    which is a wrapper for the colon refspec (a <code>source:destination</code> pair)
+    of deleting a remote branch.
     </p>
 
     <p class="nutshell">