There are two very different ways to use breath in yogic traditions.
One is what is discussed in the article (prāṇāyāma) controlling breath for health benefits and calm. Slowing the breath, holding after exhale. Often as preparation for meditation.
Another is focusing on breath as meditation practise. In that practise breath is not subject to control, it's subject of attention and focus. The breath usually calms down during meditation but it rarely slows down as much as during controlled breath exercises.
One is what is discussed in the article (prāṇāyāma) controlling breath for health benefits and calm. Slowing the breath, holding after exhale. Often as preparation for meditation.
Another is focusing on breath as meditation practise. In that practise breath is not subject to control, it's subject of attention and focus. The breath usually calms down during meditation but it rarely slows down as much as during controlled breath exercises.