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pkg/docgen/bin/sdk-introduction.md

Index: pkg/docgen/bin/sdk-introduction.md
diff --git a/pkg/docgen/bin/sdk-introduction.md b/pkg/docgen/bin/sdk-introduction.md
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@@ -1,19 +1,44 @@
 Welcome to the Dart API reference documentation,
-covering the official Dart APIs (dart:*)
-as well as other packages that live in the Dart project.
-For help using the Dart APIs, also see
-[www.dartlang.org](https://www.dartlang.org)
-pages such as the following:
+covering the official Dart API libraries.
+Some of the most fundamental Dart libraries include:
 
-  * [Programmer's Guide](https://www.dartlang.org/docs/)
-  * [A Tour of the Dart Libraries](https://www.dartlang.org/docs/dart-up-and-running/contents/ch03.html)
-  * [Dart Cookbook](https://www.dartlang.org/docs/cookbook/)
-  * [Articles](https://www.dartlang.org/articles/)
+* [dart:core](#dart:core):
+  Core functionality such as strings, numbers, collections, errors,
+  dates, and URIs.
+* [dart:html](#dart:html):
+  DOM manipulation for web apps.
+* [dart:io](#dart:io):
+  I/O for command-line apps.
+
+Except for dart:core, you must import a library before you can use it.
+Here's an example of importing dart:html, dart:math, and a
+third popular library called
+[polymer.dart](http://www.dartlang.org/polymer-dart/):
+
+    import 'dart:html';
+    import 'dart:math';
+    import 'package:polymer/polymer.dart';
+
+Polymer.dart is an example of a library that isn't
+included in the Dart download,
+but is easy to get and update using the _pub package manager_.
+For information on finding, using, and publishing libraries (and more)
+with pub, see
+[pub.dartlang.org](http://pub.dartlang.org).
+
+The main site for learning and using Dart is
+[www.dartlang.org](http://www.dartlang.org).
+Check out these pages:
+
+  * [Dart homepage](http://www.dartlang.org)
+  * [Tutorials](http://www.dartlang.org/docs/tutorials/)
+  * [Programmer's Guide](http://www.dartlang.org/docs/)
+  * [Samples](http://www.dartlang.org/samples/)
+  * [A Tour of the Dart Libraries](http://www.dartlang.org/docs/dart-up-and-running/contents/ch03.html)
   
-The API reference is automatically generated from the source code in the
+This API reference is automatically generated from the source code in the
 [Dart project](https://code.google.com/p/dart/).
 If you'd like to contribute to this documentation, see
-[Guidelines for Dart Doc Comments](http://www.dartlang.org/articles/doc-comment-guidelines/),
-[Contributing](https://code.google.com/p/dart/wiki/Contributing),
-and, if you're contributing to DOM-related docs such as dart:html,
-[Contributing HTML Documentation](https://code.google.com/p/dart/wiki/ContributingHTMLDocumentation).
+[Contributing](https://code.google.com/p/dart/wiki/Contributing)
+and
+[Writing API Documentation](https://code.google.com/p/dart/wiki/WritingApiDocumentation).