Answer:
Step-by-step explanation:
In the context of history and geology, eras and periods are both units of time used to categorize and describe long stretches of time. However, they differ in terms of their scale and scope.
An era is a major division of geologic time, usually based on the overall character of the rocks that were formed during that time. The geologic time scale is divided into four eras: the Precambrian, the Paleozoic, the Mesozoic, and the Cenozoic. Each era is characterized by major changes in the types of organisms that lived on Earth, as well as changes in the planet's climate, geology, and other physical features.
On the other hand, a period is a smaller division of time within an era. Each era is made up of several periods, which are usually named after a characteristic rock layer or a significant event that occurred during that time. For example, the Paleozoic era is divided into the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian periods. Each period is characterized by its own unique assemblage of fossil species and environmental conditions.
Overall, eras are larger and more general units of time, while periods are more specific and smaller subdivisions of eras.