Surah Yaseen contains all pillars of Islam and because of that is called the heart of the Quran. These pillars include Tawhid (Monotheism), Nabowwat (Prophethood), Adl (Justice), Imamate, Ma'ad (Resurrection).
Yā Sīn is the 36ᵗʰ sūrah of the Quran. It is regarded an earlier "Meccan surah".