Yoga's inner vocabulary — nāḍī (channel), cakra (wheel), vāyu (wind), prāṇa (breath) — reads like a scientific nomenclature, but its history is closer to sediment than to a laboratory notebook. Pick a concept on the left to see when it existed, click a band to visit that era, and watch each term either sharpen, splinter, or get borrowed for something new.
Bands are equal width for legibility — the underlying spans of time are very unequal (schematic, not linear).