Yoga is a Sanskrit word that has various meanings depending on the context of Hindu philosophy. The word is derived from the Sanskrit origin yuj which means "to unite" or "to control". Several of its translations include "union", "joining", and "conjunction". In places outside India, it is normally associated with Hatha Yoga and its asanas or positions as sort of exercise. Someone who observes yoga practices or follows the philosophy is called a Yogi or yogist in the modern times.
As people begin to practice and maybe go to a gym for a exercise class, they will discover that the old tradition of Yoga was strictly practiced by ancient gurus and sages. Somehow, Yoga is more about spiritual awareness. In Hinduism, it is also associated with one of the orthodox schools of Hindu philosophy, and to the purpose toward which that school conducts its practices. In Jainism, it points out to the sum total of all mental, physical, and verbal activities.
Several Hindu sacred writings and tantras such as the Bhagavad Gita, Srimad Bhagavatam, Hatha Yoga Pradipika, and the Shiva Samhita discuss the significant aspects of yoga. The main stems of yoga in Hindu philosophy include the Hatha Yoga, Raja Yoga, Karma Yoga, Jnana Yoga, and Bhakti Yoga. Raja Yoga is actually anthologized in the Yoga Sutras of Patanjali and is a part of the Samkhya tradition.
The Bhagavad Gita, meaning "Song of the Lord", uses the word yoga broadly in a lot of ways. Bhagavad Gita's chapter six is entirely devoted to the traditional yoga exercises and practice including meditation and features three major types of yoga such as Karma Yoga, Bhakti Yoga, and Jnana Yoga. Karma Yoga is the yoga of action, Bhakti yoga is the yoga of devotion, and Jnana yoga is the yoga of knowledge.
In the Mahabharata, the purpose of yoga is depicted as entering the realm of Brahma, as Brahman, that encompasses all things. For the bhakti schools of Vaishnavism, bhakti or service to the Svayam Bhagavan itself may be the topmost goal of the yoga practice, where the goal is to take pleasure in an eternal relationship with the Supreme Being.
Yoga works on so many levels and incorporates intense concentration on the physical and mental part of the practice. But what's great about yoga is that the more a person gets deeper into it, the more he or she can actually decide to explore the more spiritual and mystical traditions associated with it, tracing all the way back to the historical accounts of Krishna as the Supreme Being in the Bhagavad Gita.
This practice indeed, has mental, physical, emotional and spiritual benefits all just waiting to be unleashed. It's an ancient discipline intended at training the consciousness for a state of ideal spiritual insight and harmony that is actualized through the three yoga paths of actions, knowledge and devotion. Even in modern times, it can certainly make a difference.