I want to make my own Android application. I am using Ubuntu 64bit and IntelliJ. In Virtual Device Configuration, it asks me to choose a system image. All of the options have a
The fundamental difference is the CPU that is being emulated.
The decision on which to choose really depends upon your target device. ARM processors are far more prevalent, so testing your app with the ARM virtual devices often makes sense.
Another consideration is native code. If your app contains any native code, or 3rd-party libraries with native code, then your choice of virtual device is important. Native code is compiled into libraries (.so files) that are CPU-specific. Thus you would use the ARM virtual devices to test the ARM libraries in your app, and the X86 virtual devices to test the X86 libraries in your app.
A final consideration is speed of execution. X86 virtual devices will run faster on X86 desktop machines.