Some basic questions on Android downloading
<p>While downloading the things related to Android 3.0 (API 11) I downloaded all the things except</p>

<ol>
<li>Google API's</li>
<li>XOOM</li>
<li>Google USB driver </li>
</ol>

<p>i.e. through the Android SDK manager I downloaded only the below things</p>

<ol>
<li>Android SDK tools</li>
<li>SDK Platform</li>
<li>Samples for SDK </li>
</ol>

<p>Actually I wanted to download all the things under Android 3.0 but was unable to do so because of Internet and huge size of files. <br><br><b> So I want to ask what is the actual use of things which I haven't downloaded and therefore what type of application I cannot develop due to the absence of these things ?</b></p>
