Ibn Ḥajar al-ʿAsqalānī (Arabic: ابن حجر العسقلاني; 18 February 1372 – 2 February 1449 CE / 773 – 852 A.H.), or simply Ibn Ḥajar, was a classic Islamic scholar "whose life work constitutes the final summation of the science of hadith." He authored some 150 works on hadith, history, biography, exegesis, poetry, and Shafi'i jurisprudence, the most valued of which being his commentary of Sahih al-Bukhari, titled Fath al-Bari. He is known by the honorific epithets Hafiz al-Asr, Shaykh al-Islam, and Amir al-Mu'minin fi al-Hadith.

Hadith or Athar refers to what most Muslims and the mainstream schools of Islamic thought believe to be a record of the words, actions, and the silent approval of the Islamic prophet Muhammad as transmitted through chains of narrators. In other words, the ḥadīth are attributed reports about what Muhammad said and did.