Yoga is derived from the Sanskrit root "yuj" which means to connect, join or balance. The most important thing, however, is that Yoga - with its entire applications and implications - is a powerful means to an end. The ultimate end of all human pursuits is "Moksha" {Moksha is freedom from all bondage; freedom from insecurities; freedom from the clutches of desires; freedom from the sense of limitations and inadequacy; freedom from all that thwarts us on our divine journey in life.} There are many definitions of Yoga, which apply to all levels of existence and awareness. At the physical level, we need to harmonize the functions of different organs, muscles and nerves so that they do not hamper or oppose each other. Disharmony in various body parts and systems brings about inefficiency and lethargy or clumsiness. Moreover, it manifests in diseases in the body. In this context we can define Yoga as physical harmony & health and mental balance & peace.

According to the Bhagwad Gita, a very widely known classical text on Yoga, gives various definitions of Yoga.

Jyana Yoga: The Yoga committed to inquiry. Jyana in Sanskrit means "knowledge", and is often interpreted to mean "knowledge of the true self". In the Vedanta school of the Hindu religion, to know Brahman as one's own Self is jnana. To say, based on experience "I am Brahman, the pure, all-pervading Consciousness, the non-enjoyer, non-doer and silent witness," is jnana. To behold the one Self everywhere is jyana.

Karma Yoga: The Yoga committed to selfless service and Dharma which is also known as Buddhi Yoga or the "discipline of action" is based on the teachings of the Bhagavad Gita, a sacred Sanskrit scripture of Hinduism. One of the four pillars of yoga, Karma yoga focuses on the adherence to duty (dharma) while remaining detached from the reward. It states that one can attain Moksha (salvation) or love of God (bhakti) by performing their duties in an unselfish manner for the pleasure of the Supreme. Karma Yoga is an intrinsic part of many derivative types of yoga, such as Natya Yoga

Bhakti Yoga: This term within Hinduism which denotes the spiritual practice of fostering of loving devotion to God, called bhakti. Traditionally there are nine forms of bhakti-yoga. Bhakti yoga is generally considered the easiest of the four general paths to liberation, or moksha (the others being Karma, Raja and Jnana Yoga), and especially so within the current age of Kali yuga (according to the Hindu cycle of time). In scriptures such as the Bhagavata Purana, bhakti is described as a perfectional stage in itself which surpasses even moksha as a level of spiritual realisation. Hindu movements in which bhakti yoga is the main practice are called bhakti movements.The Yoga devoted to love and devotion to God.

Raja Yoga: The Yoga committed to introspection and contemplation. Thus is the system of yoga outlined by Patanjali in his Yoga Sutras. It is also sometimes referred to as Ashtanga (eight-limbed) yoga because there are eight aspects to the path to which one must attend. Raja yoga is concerned principally with the cultivation of the mind using meditation to further one's acquaintance with reality and finally achieve liberation.

Hatha Yoga: The Yoga devoted to the discipline of the body and the balance of the mental, physical and subtle forces of the body through the practice of asana and pranayama.