Historiography, writing of history , especially that based on the critical examination of sources and the synthesis of chosen particles from those sources into a narrative that will stand the test of critical methods. Two major tendencies in history writing are evident from the beginnings of the western tradition. The concept of historiography as the accumulation of records and the concept of history as storytelling , ﬁlled with explanations of cause and effect. In the 5th century BCE the Greek historians Herodotus and later , Thucydides, Emphasized ﬁrsthand inquiry in their efforts to impose a narrative on contemporary events. The dominance of Christian historiography by the 4th century introduced the idea of world history. The 19th and 20th centuries saw the development of modern methods of historical investigations based on the use of primary source materials.