diff --git a/courses.php b/courses.php
index c901de6..c3157ad 100644
--- a/courses.php
+++ b/courses.php
@@ -24,12 +24,22 @@ include "includes/navbar.html";
 <section class="teaching">
 <article>
   <header>
-    <h1>Genap 2018/2019</h1>
+    <h1>Gasal 2019/2020</h1>
   </header>
   <ol>
     <li><a href="kakom-ti/index.php">Computer Security</a></li>
     <li><a href="adminsis-ti/index.php">System Administration</a></li>
-    <li><a href="jarkom-ti/index.php">Computer Networks</a></li>
+    <li><a href="os-ti/index.php">Operating System</a></li>
+  </ol>
+</article>
+<article>
+  <header>
+    <h1>Genap 2018/2019</h1>
+  </header>
+  <ol>
+    <li>Computer Security</li>
+    <li>System Administration</li>
+    <li>Computer Networks</li>
   </ol>
 </article>
 <article>