The Yajurveda carries the formulas spoken by the priest during yajna, so its verses are arranged for use in the rite rather than for recitation alone. It comes down in two recensions, the Shukla and the Krishna Yajurveda, and the Taittiriya Samhita belongs to the latter. The Shatapatha Brahmana, attached to the Shukla recension, expands on the meaning of the rites it accompanies.
✦ Did you know
The Shri Rudram, chanted at Shiva temples across India, is not from a Purana. It sits in the Krishna Yajurveda, in the Taittiriya Samhita.
Source: Taittiriya Samhita 4.5 (Namakam) and 4.7 (Chamakam)