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chrome/common/extensions/docs/templates/articles/app_codelab.html

 <h1 id="get_ready_to_build_chrome_apps_">About this Codelab</h1>
 
 <p>The goal of this codelab is to
 get you building Chrome Apps fast.
 We&#39;ve done our best to capture some of the trickier parts
 to the development process
 keeping the samples simple and straightforward.
 Once you&#39;ve completed this codelab,
 you will have a simple Todo app.
 </p>
 
 <p>
 All sample code can be downloaded from the
 <a href="https://github.com/GoogleChrome/chrome-app-codelab">chrome-app-codelab repository</a>. 
 Each lab builds upon the previous lab's sample code.
 To see how the Todo app changes as you work through the lab,
 upload the code from the extensions management page
 and launch the app
-(see <a href="first_app.html#five">Create Your First App tutorial</a>).
+(see <a href="first_app#five">Create Your First App tutorial</a>).
 </p>
 
 <p class="note">
 <strong>Note: </strong>
 After the first launch,
 ChromeOS and Windows users can see their apps in the
 <a href="http://blog.chromium.org/2013/02/chrome-app-launcher-developer-preview.html">Chrome app launcher</a>.
 Other platforms can see installed apps on a new Chrome tab
 or by navigating to <code>chrome://extensions</code>.
 </p>
 
 <h2 id="options">Choose your framework</h2>
 
 <p>
 You can choose to write your sample Todo app
 using a preferred
-<a href="app_frameworks.html">MVC framework</a>.
+<a href="app_frameworks">MVC framework</a>.
 Starting in
-<a href="app_codelab3_mvc.html">3 - Create MVC</a>,
+<a href="app_codelab3_mvc">3 - Create MVC</a>,
 we've provided sample code in pure JavaScript
 and using
 <a href="http://angularjs.org">AngularJS</a>.
 We've also included code snippets for both versions
 throughout the codelab docs.
 As you continue through the codelab,
 make sure your sample code builds from the same version.
 </p>
 
 <p class="note">
 <strong>Want to add a framework?</strong><br>
 You can always create your own Todo app
 in a different preferred framework.
 And we would be very happy to include it
 in the sample code repository.
 </p>
 
 <h2 id="tutorial_structure">Codelab structure</h2>
 
 <ul>
-<li><a href="app_codelab1_setup.html">1 - Set Up Development Environment</a></li>
-<li><a href="app_codelab2_basic.html">2 - Create Basic App</a></li>
-<li><a href="app_codelab3_mvc.html">3 - Create MVC</a></li>
-<li><a href="app_codelab5_data.html">4 - Save and Feth Data</a></li>
-<li><a href="app_codelab6_lifecycle.html">5 - Manage App Lifecycle</a></li>
-<li><a href="app_codelab7_useridentification.html">6 - Access User's Data</a></li>
-<li><a href="app_codelab8_webresources.html">7 - Access Web Resources</a></li>
-<li><a href="app_codelab_10_publishing.html">8 - Publish App</a></li>
+<li><a href="app_codelab1_setup">1 - Set Up Development Environment</a></li>
+<li><a href="app_codelab2_basic">2 - Create Basic App</a></li>
+<li><a href="app_codelab3_mvc">3 - Create MVC</a></li>
+<li><a href="app_codelab5_data">4 - Save and Feth Data</a></li>
+<li><a href="app_codelab6_lifecycle">5 - Manage App Lifecycle</a></li>
+<li><a href="app_codelab7_useridentification">6 - Access User's Data</a></li>
+<li><a href="app_codelab8_webresources">7 - Access Web Resources</a></li>
+<li><a href="app_codelab_10_publishing">8 - Publish App</a></li>
 </ul>