Lord Shiva is also referred to as Adiyogi Shiva, which means “the first yogi." As per the scriptures and its beliefs, Lord Shiva is the father of Yoga. Shiva attained the level of full enlightenment around 15 thousand years ago, according to a poem written at that time. With the passage of time and years, yoga evolved into what is now known as modern yoga. Modern yoga incorporates a variety of methods, asanas (postures), and mindfulness activities evolved from the yoga school’s beliefs, teachings, and practices.

But Patanjali is often regarded as the father of modern yoga, according to several theories. Patanjali’s Yoga Sutras are a compilation of aphoristic Sanskrit sutras on the philosophy and practice of ancient yoga. These writings mention but do not elaborate on the 12 postures: Padma asana, Veera asana, Bhadra asana, svastika asana, danda asana, sopasraya asana, paryanka asana, kraunchanishada asana, hastanishada asana, ushtranishada asana, samasansathana asana.

Patanjali’s Yoga Sutras are a revered text among those who practice modern yoga.

Tirumalai Krishnamacharya is also regarded as the father of modern yoga in various regions of India. He was a yoga instructor, ayurvedic healer, and scholar from India. Krishnamacharya is widely recognized as one of the twentieth century’s most important yoga instructors.

More Info: en.wikipedia.org