Imam al-Bukhari

Muhammad ibn Isma'il ibn Ibrahim al-Bukhari al-Ju'fi was born in Bukhara (Uzbekistan) and became the greatest hadith scholar of all time. He began traveling for knowledge at age 16 and spent decades gathering hadiths across the Islamic world. He memorized over 600,000 hadiths with their chains and selected 7,275 unique hadiths (with repetitions: ~9,082) for his Sahih — spending 16 years on its composition and reportedly making ghusl and praying two rak'ahs before writing each hadith. His Jami' al-Sahih (known as Sahih al-Bukhari) is universally accepted as the most rigorously authenticated hadith collection and the most authentic book after the Quran. He also wrote al-Tarikh al-Kabir (a 9-volume biographical dictionary of narrators). He died in Khartank, near Samarqand, in 256 AH.