How did people find about past?

People found out about past by learning about the History about how people lived by excavating grounds and finding stone weapons and pottery pieces which were excavated and archaelogists fixed them and thought how they used those , For example stone weapons , some were used to killed  some were used to light fire , even fire was invented by an unknown person who rubbed two stones together and spark produced like that somehow hominids invented fire .
   
Hope it Helped you .. 

Thanks Regards
 Arqk Maheshwary .