diff --git a/includes/courses.php b/includes/courses.php
index ade0f3a..aebfc7b 100644
--- a/includes/courses.php
+++ b/includes/courses.php
@@ -6,7 +6,7 @@
     <li>|</li>
     <li><a href="../adminsis-ti/">SysAdmin</a></li>
     <li>|</li>
-    <li><a href="../jarkom-ti/">CompNet</a></li>
+    <li><a href="../os-ti/">OS</a></li>
   </ul>
 </nav>
 
diff --git a/index.php b/index.php
index a404cb9..9909e46 100644
--- a/index.php
+++ b/index.php
@@ -50,9 +50,9 @@ include "includes/quotes.php";
   <article>
     <header>
       <h3>My classes next semester</h3>
-      <span><time datetime="2019-01-30">January 30, 2019</time></span>
+      <span><time datetime="2019-08-20">August 20, 2019</time></span>
     </header>
-    <p>I will be teaching  Computer Network, System Administration, and Computer Security.</p>
+    <p>I will be teaching  Operating System, System Administration, and Computer Security.</p>
   </article>
 </section>
 <?php
diff --git a/os-ti/index.php b/os-ti/index.php
index f00ce0d..4dd64d5 100644
--- a/os-ti/index.php
+++ b/os-ti/index.php
@@ -24,7 +24,8 @@ include "../includes/courses.php";
     <h3>Jadwal</h3>
   </header>
   <aside>
-    <p>Grup A<br/>Hari Kamis<br/>Jam 13.30 - 16.20<br/>Ruang </p>
+    <p>Grup A<br/>Hari Kamis<br/>Jam 07.30 - 16.20</p>
+	<p>Grup C<br/>Hari Rabu<br/>Jam 13.30 - 16.20</p>
   </aside>
 </section>
 <section class="classinfo">
@@ -32,7 +33,7 @@ include "../includes/courses.php";
     <header>
       <h1>PEMBERITAHUAN</h1>
     </header>
-    <p>Bagi yang hendak mengambil matakuliah ini, Anda <strong>diwajibkan memiliki dan membawa buku Operating System Concepts di setiap pertemuan</strong>. Tidak akan disediakan slide materi untuk perkuliahan ini, karena semua materi sudah ada di buku.</p>
+    <p>Bagi yang hendak mengambil matakuliah ini, Anda <strong>diwajibkan memiliki akun Moodle.</p>
   </section>
   <section class="description">
     <header>
@@ -57,7 +58,7 @@ include "../includes/courses.php";
     <li>Main Memory</li>
     <li>Virtual Memory</li>
     <li>Mass-Storage Structure</li>
-    <li>File System Interface + Implementation</li>
+    <li>File System</li>
     <li>Input/Output System</li>
     <li>Virtual Machines</li>
     <li>Special Topic</li>
@@ -69,7 +70,7 @@ include "../includes/courses.php";
     <h1>REFERENSI</h1>
   </header>
   <ol>
-    <li><a href="http://www.os-book.com/">Operating System Concepts 9<sup>th</sup> Edition (Avi Silberschatz, Peter Baer Galvin, Greg Gagne - John Wiley &amp; Sons, Inc)</a></li>
+    <li><a href="http://www.os-book.com/">Operating System Concepts 10<sup>th</sup> Edition (Avi Silberschatz, Peter Baer Galvin, Greg Gagne - John Wiley &amp; Sons, Inc)</a></li>
   </ol>
 </section>
 <?php