The earliest works of Japanese literature include the Kojiki and Nihon Shoki chronicles and the Man'yōshū poetry anthology, all from the 8th century and written in Chinese characters. In the early Heian period, the system of phonograms known askana (Hiragana and Katakana) was developed. The Tale of the Bamboo Cutter is considered the oldest Japanese narrative. An account of Heian court life is given in The Pillow Book by Sei Shōnagon, while The Tale of Genji by Murasaki Shikibu is often described as the world's first novel.