diff --git a/docs/filter-howto.txt b/docs/filter-howto.txt
index 3acd813..52bfd5f 100644
--- a/docs/filter-howto.txt
+++ b/docs/filter-howto.txt
@@ -34,6 +34,7 @@ start blocking some sites.
 
 Example "filter" file entries:
 
+# This is a comment
 bannerads.zwire.com
 ad.doubleclick.net
 ads.fortunecity.com
@@ -49,4 +50,4 @@ Copyright (c) 2002  Patrick L.  McGillan <pmcgillan@dwx.com>
 
 This document is released under the same copyright license as
 tinyproxy.  You should have found a COPYING file in the top level
-directory of this distribution which contains the current license.
\ No newline at end of file
+directory of this distribution which contains the current license.