Answer:
It is simplistic to describe history as "what happened in the past" because it's is not just an accumulation of facts. History goes beyond examining the records of events that have occurred.
It also involves studying to know why those events occurred. When the why is understood, then learning takes place and knowledge gained can be used to repeat and improve upon successes whilst preventing and or correcting mishaps.
This is important because the future is an accumulation of past and present occurrences.
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