The archean age was an age of time that lasted from 3.8-2.5 billion years ago. The earth is approximately 4.6 billion years old so you can see that the archean age was near the beginning of earth’s history. The earth was very different at that time than it is now. The atmosphere was composed of toxic gases with little oxygen at the beginning of the archean age and therefore the vast array of life on earth that we are familiar with now was nonexistent. At the beginning of the archean age the major life form was bacteria. The continental plates were also beginning to form at this time meaning the earth’s surface also looked vastly different than it does today. It was not until much later in earth’s history that the earth began to shift into what we see around us now.
Source: public domain photo obtained from wikipedia