The Cenozoic Era is the most recent geological period, spanning from 66 million years ago to the present day. It is divided into two periods: the Neogene and the Tertiary. The Neogene period is the younger of the two, lasting from 23 million years ago to 2.6 million years ago. The Tertiary period is the older of the two, lasting from 65 million years ago to 23 million years ago. Both of these periods are part of the Cenozoic Era.