Imām Muslim's full name is Abu al-Husayn Muslim ibn al-Hajjāj ibn Muslim ibn Warat al-Qushayri al- Naysaburi (206-261 AH/821-875 AD). Imām "Muslim," as his nasba shows, belonged to the Qushayr tribe of the Arabs, an offshoot of the great clan of Rabi'a.
He was born in Naysabur (Nishapur) in 206/821. His parents were righteous people who left such an indelible impression on his mind that he spent his life as a God-fearing person and always adhered to the path of righteousness.
Imām Muslim travelled widely to collect hadith in Arabia, Egypt, Syria and Iraq, where he attended the lectures of some of the prominent Muhadith of his time: Isḥāq b. Rāḥawayh, Aḥmad bin Hanbal, 'Ubaydullah al-Qawariri, Qutaiba bin Sa’id, 'Abdullah ibn Maslama, Harmalah bin Yahya, and others. After completing his education, he settled down at Nishapur. There he came into contact with Imām al-Bukhārī. Imām Muslim was impressed with Imām al-Bukhārī's knowledge that he kept himself attached to him up to the end of his life. Another muhaddith that influenced Imam Muslim was Muhammad ibn Yahya al-Dhuhali and he attended his lectures regularly, but when the difference of opinion between Muhammad b. Yahya and Imam Bukhari on the issue of the creation of the Qur'an sharpened into hostility, Imam Muslim sided with Imam Bukhari and abandoned Muhammad b. Yahya altogether. He was therefore a true disciple of Imām al-Bukhārī. 
Many students learned the Science of Hadith from Imam Muslim. Those who became famous and occupied a prominent position are: Abu Hatim Razi, Musa bin Harun, Ahmad bin Salamah, Abu `Isa Tirmidhi, Abu Bakr bin Khuzaimah, Abu `Awanah and Hafiz Dhahbi.
His well known books include: al-Jaami’ al-Saheeh; al-Kuna wa’l-Asma’; al-Tabaqaat; al-Tamyeez; and al-Munfaridaat wa’l-Wahdaan.
For more information on the lives of these two imams, see their biographies in Siyar A’laam al-Nubala’, 12/391-471; 557-580. 
Imam Muslim compiled many books and treatises on Hadith, the most important of his works is the compilation of the Hadith collection Al-Jami `As-Sahih, which is famous by the name of Sahih Muslim. Some scholars of Hadith opine that in some respects it is the best and most authentic collection of Ahadith. Imam Muslim laboriously collected 3,00,000 Ahadith, but after a critical study, he selected only 4,000 Ahadith for this collection. Other contributions of Imam Muslim on the subject of Hadith are: Al-Kitab Al-Musnad Al-Kabir Alar-Rijkl, Al-Jami'Al-Kabir, Kitab-ul-Asma' wal-Kuna, Kitab-ul'Ilal, Kitab-ul-Wahdan, etc. 
Imam Muslim strictly observed many principles of the science of Hadith, which had been slightly ignored by his great teacher Imam Bukhari (May Allah have mercy on both of them).
Imam Muslim lived for fifty-five years. He spent most of his time in learning Hadith, in its compilation, in its teaching and transmission. He always remained absorbed in this single pursuit and nothing could distract his attention from this pious task. He died in 261/875, and was buried in the suburbs of Nishapur. 
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