In India we say traditionally that creation and destruction are two parts of the same coin. The moment something gets created; it can only move towards becoming nothing. And to become the original nature is Yoga. So yoga is an integral part of everyone’s life existentially.
The word Yoga becomes relevant when it finds a conscious expression. To put it in to our conscious framework; one person’s work surpasses even imagination. He is the first yogi or Adi-yogi. 15000 years back this person appeared in the upper region of Himalayas and transmitted the whole mechanics of life to 7 people, now revered as Sapta Rishis. Since then this knowing transmuted to various forms and dimensions and is still present in various cultures of the world.
Yogis and Gurus of different times use a minuscule of this science and give it to people of that era. In that lineage comes millions of Yogis, Siddhas which contributed in their own ways to this already complete science. In this lineage also come Rishi Patanjali whome we consider the Father of present form of yoga.