Vedas are the ancient texts of knowledge transferred from God to learned sages through thousand years of meditation and considered as sacred in India and known world over as the source of knowledge. Yoga is practice of vedic knowledge to connect individual consciousness (inner self) with universal consciousness (Brahman), which helps to maintain harmony in nature. As per Bhagbat Gita, there are three types of Yoga, Jnyana Yoga, Karma Yoga and Bhakti Yoga.
Through Jnyana Yoga, or yoga of knowledge, a person reaches at the level of self realization, self consciousness and union of inner self with all through knowledge of Veda. All sages do meditation for thousand years in search of this knowledge. The Maharshis, Adi Shankaracharya and many more sages were practicing Jnyana Yoga.
Bhakti Yoga is Love for Self, or Brahma, which is Supreme Being and universally present, it is manifestation of Divinity. It is surrendering the inner self before divinity and feeling presence of Supreme Being. It is represented by Vishnu, Shiva etc. In Bhagvat Gita it is narrated as the supreme of three yogic form where Krishna Tells Arjuna that I am the Brahma inside every Body, as Bhisma, as Yudhisthir, as Arjuna, as Duryodhana,as Drona etc. So human beings are part of that supreme being and after salvation they become part of the supreme being.
Karma Yoga is the Yoga of Action and through this yoga, human beings align the actions, the rituals they follow with the supreme being through the path of knowledge and divinity. It is Unity of Inner self with worldly knowledge. The people practicing Karma Yoga, they just perform their duty for the universal wellbeing without any expectation of result and leaves it with Divinity.
Through Practice of Yoga of different forms, the soul or atman is enlightened to work with its fullest form, which we say self actualization for the benefit of mass and through this action, soul is united with universal power, fully surrendered to the divinity.
Lord Shiva is Adiyogi of Yoga. Before fifteen thousand years, when Shiva got the full enlightenment, he emerged himself to a different form of dance and after that for years he looked just standing still either he was calm or he was dancing in such a high speed that it was not visible to the eyes of the people. Seven sages wanted learn this dance form and they meditated for around hundred years and once on a full moon day, when Shiva opened his eyes, he could see those sages glowing to receive knowledge and he transferred seven different forms of yoga to seven sages, so this Purnima is known as Guru Purnima. After that those Saptarshi were respected in the society a lot. After the transfer of knowledge Shiva was known as Adiguru. Those seven sages went to seven different directions and those seven forms are considered as basic forms of yoga.
In the year, 2014, United Nations General Assembly had passed 21st June as the International Yoga Day, on request of Honourable Prime Minister of India, and which was unanimously accepted by considering the Universality of Yoga practice in the Mind, Body and Soul. Happy International Yoga Day to all.