Question

What are the the four main periods of time of Earth’s history from oldest to youngest?

Answer 1

The four main ERAS are, from oldest to youngest: PreCambrian, Palaeozoic, Mesozoic and Cenozoic. Periods are a finer subdivision in the geological time scale.

Explanation:

However, more recently the Pre-Cambrian Era has been subdivided into the Proterozoic, Archean and Hadean Eras.