v4 Support Library

This library is designed to be used with Android 1.6 (API level 4) and higher. It includes the largest set of APIs compared to the other

libraries, including support for application components, user

interface features, accessibility, data handling, network

connectivity, and programming utilities.

v7 Libraries

There are several libraries designed to be used with Android 2.1 (API level 7) and higher. These libraries provide specific feature sets and

can be included in your application independently from each other.

v7 appcompat library

This library adds support for the Action Bar user interface design pattern.

Note:

This library depends on the v4 Support Library. If you are using Ant or Eclipse, make sure you include the v4 Support Library as part

of this library’s classpath.

所以是的，你需要两个罐子，如果你想使用v7。

更新android-support-v13.jar

v13 Support Library

This library is designed to be used for Android 3.2 (API level 13) and higher. It adds support for the Fragment user interface pattern

with the (FragmentCompat) class and additional fragment support

classes

当你看到package details它有一个类FragmentCompat定义中给出。所以它没有所有类的appcompat库。