Android emulator is used to run, debug and test Android applications. If you do not have a real device, then this application can be the best way to run, debug and test.
It uses an open source processor emulator technology called QIMU
The emulator tool enables you to start the emulator from the command line. You must write:
In case of Eclipse IDE, you can create AVD by Window menu > AVD Manager > New.
You can see the Android emulator, it displays the output of the Hello Android instance, In the given below snapshot: