The science of evaluating the character and reliability of Hadith narrators is known as

Ilm al-Rijal, also known as Ilm al-Jarh wa al-Ta'dil, is the science that deals with the critical evaluation of Hadith narrators to determine their trustworthiness, memory, and moral character. Scholars used this science to accept or reject narrations. Fiqh al-Hadith deals with understanding the legal implications of Hadiths, while Tafsir concerns Qur'anic exegesis.