Samvasaran (also spelled Samavsharan or Samavasarana) is the divine preaching hall or assembly that appears after a Tirthankara attains kevala jnana (omniscience). It is the universal “refuge to all” where the Tirthankara delivers sermons to all beings—humans, animals, and even celestial beings—in a manner understood by each being. It is described as a grand, circular pavilion with a special seating arrangement and a throne for the Tirthankara, accompanied by Ganadharas (chief disciples) and various beings in successive halls. The essence is the open, compassionate sharing of pure Dharma with all life, without discrimination. There are minor differences in description between Digambara and Śvetāmbara traditions in some details, but the core idea remains the same: a universal teaching sphere accessible to all. You can read more here