diff --git a/system/libraries/Cache/drivers/Cache_apc.php b/system/libraries/Cache/drivers/Cache_apc.php
index 07ea8f4..fb8df03 100644
--- a/system/libraries/Cache/drivers/Cache_apc.php
+++ b/system/libraries/Cache/drivers/Cache_apc.php
@@ -97,7 +97,7 @@
 	 *
 	 * @param	string	$id	Cache ID
 	 * @param	mixed	$data	Data to store
-	 * @param	int	$ttol	Length of time (in seconds) to cache the data
+	 * @param	int	$ttl	Length of time (in seconds) to cache the data
 	 * @param	bool	$raw	Whether to store the raw value
 	 * @return	bool	TRUE on success, FALSE on failure
 	 */
diff --git a/system/libraries/Session/Session.php b/system/libraries/Session/Session.php
index 1bdc6e5..3b391a8 100644
--- a/system/libraries/Session/Session.php
+++ b/system/libraries/Session/Session.php
@@ -730,7 +730,7 @@
 	 *
 	 * Legacy CI_Session compatibility method
 	 *
-	 * @param	mixed	$data	Session data key(s)
+	 * @param	mixed	$key	Session data key(s)
 	 * @return	void
 	 */
 	public function unset_userdata($key)
diff --git a/system/libraries/Upload.php b/system/libraries/Upload.php
index f241837..fa36505 100644
--- a/system/libraries/Upload.php
+++ b/system/libraries/Upload.php
@@ -286,7 +286,7 @@
 	/**
 	 * Constructor
 	 *
-	 * @param	array	$props
+	 * @param	array	$config
 	 * @return	void
 	 */
 	public function __construct($config = array())