diff --git a/How-to-whitelist-a-web-site.md b/How-to-whitelist-a-web-site.md
index 3d0bab8..2d29584 100644
--- a/How-to-whitelist-a-web-site.md
+++ b/How-to-whitelist-a-web-site.md
@@ -8,14 +8,17 @@ The feature is already available, it is the big power button: it serves to white
 
 All whitelist directives are matched against the URL address of web pages.
 
-As of version 0.8.2.0, the whitelist directive syntax is split into two classes:
+As of version 0.8.2.0, the whitelist directive syntax is split into three classes:
 - Plain
 - Complex
+- Comment
 
 Plain syntax is when using only hostname label(s), which means only the hostname portion of a URL will be taken into account. With plain syntax, the matching is performed by comparing the right-most portion of the page hostname with the whitelist directive. Wildcards are not allowed when using plain syntax.
 
 Complex syntax occurs if and only if at least one `/` appears in a whitelist directive. Optionally, wildcard `*` can be used with complex directives for more flexibility.
 
+A comment is a line prefixed with `#`. Comments are ignored by µBlock.
+
 If no `/` appears in a whitelist directive, and if the directive contains characters which are not allowed for plain hostname, then the whitelist directive will be commented out and ignored by µBlock.
 
 #### Plain hostname