Herodotus is often considered the "father of history." Living in the 5th century BC, he was a contemporary of Thucydides. The Histories is his most famous book, mostly about the origins of the Greco-Persian wars. In it, Herodotus recounts history with a mixture of myth, legends, gossip and hearsay that makes them significantly inaccurate. Nevertheless, much of what he wrote about has been confirmed by archaeologists.
Thucydides, on the other hand, claimed to be very careful about his evidence-gathering and tried to apply strict standards of impartiality. His book History of the Peloponnesian War is more factually rigorous than that of Herodotus. Therefore, Thucydides is often named the "father of scientific history."