Till now Azioc meant just a music group but it is not just that. Azoic is also the name of first era of our planet Earth.

Era, Period, Epoch
Earth is 4.5 billion years old and this time has been divided in to one or more Era. And each one of these Era is further divided in to Periods. And each period is in turn divided in to Epoch.

Azoic is the first Era, from 4.5 to 4.0 billions years

Archean is the second Era, from 4.0 to 2.5 billions years

Proterozoic is the third Era, from 2.5 to 0.5 billions years

Paleozoic is the fourth Era, from 0.5bill to 250million years

Mesozoic is the fifth Era, from 250 to 65 million years

Cenozoic is the sixth Era, from 65 million years to till today.

Two consecutive Eras differ fundamentally. And there are totally six Era.