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

 <meta name="doc-family" content="apps">
 <h1>What Are Chrome Apps?</h1>
 
 <p>
 Chrome Apps deliver an experience as capable as a native app,
 but as safe as a web page.
 Just like web apps,
 Chrome Apps are written in HTML5, JavaScript, and CSS.
 But Chrome Apps look and behave like native apps,
 and they have native-like capabilities
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 Once a user installs an app, they have full control over the app's lifecycle.
 Apps open and close quickly,
 and the system can shut apps down at any time to improve performance.
 Users can fully uninstall apps.
 </p>
 
 <p>
 Without any effort on your part, your apps will launch offline.
 But you will need to put some effort into making sure user data is stored locally while offline
 and then synced back up to your data server once online
-(see <a href="offline_apps.html">Offline First</a>).
+(see <a href="offline_apps">Offline First</a>).
 </p>
 
 <h2 id="develop">How to develop them</h2>
 
 <p>
 Chrome Apps are modified web apps.
 You use the same code, frameworks, and tools of the web platform to write your apps.
 Some browser features have been removed, other web APIs have been disabled
 or changed to improve security and programming practices.
 </p>
 
 <p>
 New features have been added to help you build more native-like apps.
 The app container and programming models control how Chrome Apps look and behave.
 These models aim to provide users with a more native experience.
 Powerful APIs have been added so your apps can have native-like capabilities,
 and a serious security model is enforced to make sure these APIs are not abused.</p>
 
 <p>
 To learn more about how to develop Chrome Apps:
 </p>
 
 <ul>
         <li>
-                <a href="app_architecture.html">Understanding the Architecture</a>
+                <a href="app_architecture">Understanding the Architecture</a>
                 introduces the app container, programming, and security models.
         </li>
         <li>
-                <a href="app_lifecycle.html">The Fundamentals</a>
+                <a href="app_lifecycle">The Fundamentals</a>
                 shows how to use this architecture and how to build
                 for offline, manage data, and embed external content.
         </li>
         <li>
-                <a href="app_network.html">Advanced Technologies</a>
+                <a href="app_network">Advanced Technologies</a>
                 shows how to use the powerful network and hardware APIs.
         </li>
         <li>
-                <a href="app_deprecated.html">Disabled Features</a>
+                <a href="app_deprecated">Disabled Features</a>
                 describes the web features that have been disabled
                 and what to use in their place, where relevant.
         </li>
 </ul>
 
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