--- title: File System API guide slug: WebGuide/API/File_System translation_of: Web/API/File_and_Directory_Entries_API/Introduction translation_of_original: WebGuide/API/File_System --- <p>{{ SeeCompatTable() }}</p> <p>The File System API simulates a local file system that web apps can navigate around. You can develop apps that can read, write, and create files and directories in a virtual, sandboxed file system.</p> <p>The asynchronous API methods return without blocking the calling thread. The asynchronous API doesn't give you data by returning values; instead, you have to pass a callback function. The synchronous API is intended to be used inside <a href="/en/DOM/Worker" title="Worker">WebWorkers</a>.</p> <p>For an overview of the File System API, see the following articles:</p> <p>{{ListSubpages}}</p> <h2 id="Browser_Compatibility" name="Browser_Compatibility">Browser compatibility</h2> <p>{{ CompatibilityTable() }}</p> <div id="compat-desktop"> <table class="compat-table"> <tbody> <tr> <th>Feature</th> <th>Chrome</th> <th>Firefox (Gecko)</th> <th>Internet Explorer</th> <th>Opera</th> <th>Safari (WebKit)</th> </tr> <tr> <td>Asynchronous API</td> <td>13 {{ property_prefix("webkit") }}</td> <td>{{ CompatNo() }}</td> <td>{{ CompatNo() }}</td> <td>15 {{ property_prefix("webkit") }}</td> <td>{{ CompatNo() }}</td> </tr> <tr> <td>Synchronous API</td> <td>13 {{ property_prefix("webkit") }}</td> <td>{{ CompatNo() }}</td> <td>{{ CompatNo() }}</td> <td>15 {{ property_prefix("webkit") }}</td> <td>{{ CompatNo() }}</td> </tr> </tbody> </table> </div> <div id="compat-mobile"> <table class="compat-table"> <tbody> <tr> <th>Feature</th> <th>Android</th> <th>Chrome for Android</th> <th>Firefox Mobile (Gecko)</th> <th>IE Phone</th> <th>Opera Mobile</th> <th>Safari Mobile</th> </tr> <tr> <td>Asynchronous API</td> <td>{{ CompatNo() }}</td> <td>0.16{{ property_prefix("webkit") }}</td> <td>{{ CompatNo() }}</td> <td>{{ CompatNo() }}</td> <td>14 {{ property_prefix("webkit") }}</td> <td>{{ CompatNo() }}</td> </tr> <tr> <td>Synchronous API</td> <td>{{ CompatNo() }}</td> <td>0.16{{ property_prefix("webkit") }}</td> <td>{{ CompatNo() }}</td> <td>{{ CompatNo() }}</td> <td>14 {{ property_prefix("webkit") }}</td> <td>{{ CompatNo() }}</td> </tr> </tbody> </table> </div> <h2 id="See_also">See also</h2> <ul> <li><a href="/en-US/docs/Web/Reference/File_System_API" title="/en-US/docs/Web/Reference/File_System_API">File System API reference</a></li> <li>Specification: {{ spec("http://dev.w3.org/2009/dap/file-system/pub/FileSystem/", "File API: Directories and System Specification", "WD") }}</li> </ul>