What is the difference between the Intel x86 Atom and Atom_64 system images?

Question

I am using the Android SDK Manager to install the system image for the Android M Preview. However, I noticed that there are two separate images for the x86 platform.

Answer 1

i have tried both and x86_64 happens to be a little slower than x86. what i found out after a little research is that x86 can run on 32 bit based instruction set and 64 bit based while x86_64 runs only on 64 bit which needs somekind of more decoding...

you can also check here https://developer.android.com/ndk/guides/x86-64.html for more info..