diff --git a/general-patterns/built-in-prototypes.html b/general-patterns/built-in-prototypes.html
index c01f6fe..6b2a215 100644
--- a/general-patterns/built-in-prototypes.html
+++ b/general-patterns/built-in-prototypes.html
@@ -19,8 +19,8 @@
 			 *    the code or already part of the JavaScript engine of one of the browsers you support.
 			 * 3. You clearly document and communicate the change with the team.
 			 */
-			if (typeof Object.protoype.myMethod !== "function") {
-				Object.protoype.myMethod = function () {
+if (typeof Object.prototype.myMethod !== "function") {
+   Object.prototype.myMethod = function () {
 					// implementation...
 				};
 			}