History by period

Historical Eras, or classification of history, culture, and such into thematic groups involving time, so as to generate a history by period are intellectual constructs (categories) consisting of certain sets of common characteristics used by researchers, teachers, and academics when communicating about the past, it's characteristics and attributes, and the like. These are loosely defined terms in a general sense and the meaning of a term used by a sociologist may not agree with the definition as applied by a historical archeologist or historian or literature professor as differing disciplines generally look toward classification factors inside their own fields and characteristics understudy within those needs.
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