Muslim ibn al-Hajjaj was a prominent Islamic scholar born in 821 CE in Nishapur, Persia. He is best known for compiling one of the most authentic collections of Hadith, which are the sayings and actions of the Prophet Muhammad. His work, known as Sahih Muslim, is considered one of the two most reliable collections of Hadith in Sunni Islam, alongside Sahih al-Bukhari. Muslim dedicated his life to the study and verification of Hadith, traveling extensively across the Islamic world to gather authentic narrations. His rigorous methodology in evaluating the credibility of narrators set a standard for future scholars in the field of Hadith studies. His contributions have had a lasting impact on Islamic jurisprudence and theology.