The Mesolithic is the era between the Paleolithic and the Neolithic.

The Azuchi-Momoyama period, also known as the Oda-Nobunaga period, was a very important time in Japanese history.

The Azuchi-Momoyama period was a very important time in Japanese history.

Tin is a very soft metal, mainly used as solder.

The Triassic period is one of the geological ages, referring to the period from about 252 million years ago to about 251 million years ago.

At what point in Earth's history does the Triassic period fall?

The Quaternary is the most recent era in Earth's history.

The Devonian period was a very important time in the history of the Earth.

The Triassic period is one of the geological ages, referring to the period from about 252 million years ago to about 200 million years ago.

The Ordovician, an era name used in paleontology, is now called the Ordovician.