What is the difference between "Intel Atom Image", "Google APIs Intel Atom image" and "Google play Intel Atom Image"?

In the Android SDK manager I can see 3 types of Intel Atom image. Can someone explain the main difference between "Intel Atom Image", "Google APIs Intel Atom image" and "Google Play Intel Atom Image"?

A "Google APIs" image includes the Play services that many apps rely on but does not include the Play Store app

A "Google Play" image includes both the Play Store app and the Play services

A plain "Intel Atom Image" has neither the Play Store nor the Play services. It is an unaltered build from the Android Open Source Project with no additional apps added. It is good for testing apps that you intend to have no Google dependencies and, as it is a "rooted" image, for testing apps that require root access.

For Google's description, see Create and manage virtual devices | Android Developers