diff --git a/contributing.md b/contributing.md
index b6d486d..29673aa 100644
--- a/contributing.md
+++ b/contributing.md
@@ -20,7 +20,7 @@
 
 ### PHP Style
 
-All code must meet the [Style Guide](http://codeigniter.com/user_guide/general/styleguide.html), which is
+All code must meet the [Style Guide](http://ellislab.com/codeigniter/user-guide/general/styleguide.html), which is
 essentially the [Allman indent style](http://en.wikipedia.org/wiki/Indent_style#Allman_style), underscores and readable operators. This makes certain that all code is the same format as the existing code and means it will be as readable as possible.
 
 ### Documentation
diff --git a/system/core/Common.php b/system/core/Common.php
index e340931..7f27081 100644
--- a/system/core/Common.php
+++ b/system/core/Common.php
@@ -124,7 +124,7 @@
 	 *
 	 * @param	string	the class name being requested
 	 * @param	string	the directory where the class should be found
-	 * @param	string	the class name prefix
+	 * @param	string	an optional argument to pass to the class constructor
 	 * @return	object
 	 */
 	function &load_class($class, $directory = 'libraries', $param = NULL)
diff --git a/system/core/Model.php b/system/core/Model.php
index 9485ec2..9736faa 100644
--- a/system/core/Model.php
+++ b/system/core/Model.php
@@ -59,6 +59,10 @@
 	 */
 	public function __get($key)
 	{
+		// Debugging note:
+		//	If you're here because you're getting an error message
+		//	saying 'Undefined Property: system/core/Model.php', it's
+		//	most likely a typo in your model code.
 		return get_instance()->$key;
 	}
 
diff --git a/system/helpers/html_helper.php b/system/helpers/html_helper.php
index d8c3e6d..e8cef37 100644
--- a/system/helpers/html_helper.php
+++ b/system/helpers/html_helper.php
@@ -292,7 +292,7 @@
 		}
 		else
 		{
-			if ( ! preg_match('#^([a-z]+:)?//#i', $href))
+			if (preg_match('#^([a-z]+:)?//#i', $href))
 			{
 				$link .= 'href="'.$href.'" ';
 			}