The Yajurveda is the knowledge of sacrifice or sacrifice texts and formulas as distinguished from the Rigveda. It has two Samhitas - Taittiriya and Vajasaneyi Samhita known as Black (Krishna) and White (Shukla) Yajurveda. The Vajasaneyi Samhita is planned in a more systematic and orderly manner than the other. It is actually a hand-book or manual for the Adhvaryu priests who specialized in conduction sacrifices. The important sacrifices are dealt with Ashvamedha (horse-sacrifice), Purushamedha (Human-sacrifice) and Darsa Purnamasa (full and new moon).