page.title=The Android Source Code
@jd:body

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<p>
Android is an open-source software stack created for a wide array of devices
with different form factors. The primary purposes of Android are to create an
open software platform available for carriers, OEMs, and developers to make
their innovative ideas a reality and to introduce a successful,
real-world product that improves the mobile experience for users.
</p>

<p>
We also wanted to make sure there was
no central point of failure, where one industry player could restrict or
control the innovations of any other. The result is a full, production-quality
consumer product with source code open for customization and porting.
</p>

<div class="figure" style="width:700px">
  <img src="{@docRoot}images/android_framework_details.png" alt="Android framework details" height="483px" />
  <p class="img-caption">
    <strong>Figure 1.</strong> Android stack
  </p>
</div>

<h2 id="governance-philosophy">Governance Philosophy</h2>
<p>Android was originated by a group of companies known as the Open
Handset Alliance, led by Google. Today, many companies -- both original members
of the OHA and others -- have invested heavily in Android. These companies have
allocated significant engineering resources to improve Android and bring Android
devices to market.
</p>
<p>The companies that have invested in Android have done so on its merits
because we believe an open platform is necessary. Android is
intentionally and explicitly an open-source -- as opposed to a free software --
effort; a group of organizations with shared needs has pooled
resources to collaborate on a single implementation of a shared product.
The Android philosophy is pragmatic, first and foremost. The objective is
a shared product that each contributor can tailor and customize.</p>

<p>Uncontrolled customization can, of course, lead to incompatible
implementations. To prevent this, the Android Open Source Project also maintains the <a href="{@docRoot}compatibility/index.html">Android
Compatibility Program</a>, which spells out what it means to be "Android
compatible" and what is required of device builders to achieve that status.
Anyone can (and will!) use the Android source code for any purpose, and we
welcome all legitimate uses. However, in order to take part in the shared
ecosystem of applications we are building around Android, device builders
must participate in the Android Compatibility Program.</p>

<p>The Android Open Source Project is led by Google, who
maintains and further develops Android.
Although Android consists of multiple subprojects, this is strictly a
project management technique. We view and manage Android as a single,
holistic software product, not a "distribution", specification, or collection
of replaceable parts. Our intent is that device builders port
Android to a device; they don't implement a specification or curate a
distribution.</p>