AMD & AMD2

Are AMD & AMD2 the same? What socket is AMD2?

I'm in the market for a Socket 939 compatible motherboard, but many of
the motherboards I have looked at say in the title "AMD2". However,
whenever I read the specifications I see something like this:

CPU Socket: Type Socket AM2
CPU Type: Athlon 64 X2 / Athlon 64 / Sempron

So, when I see the "Athlon 64" I become a bit confused. I'm not sure
if I should buy the motherboard because it clearly states that it is
compatible with AMD2.

.