Yoga encompasses much more than physical postures. Educational overviews often describe four overlapping approaches within Indian religious traditions.
Karma-yoga emphasises responsible action without selfish attachment to outcomes. Jñāna-yoga focuses on spiritual knowledge and enquiry. Rāja or aṣṭāṅga yoga develops a disciplined approach to meditation and the mind. Bhakti-yoga centres on loving devotion and service to the divine.
Haṭha yoga commonly involves physical and breathing practices, though schools differ. Postures alone do not define bhakti.
In the Gauḍīya Vaiṣṇava understanding followed by ISKCON, devotion to Krishna holds a central place. This is a theological perspective, not a scientific ranking of spiritual traditions.
The approaches may overlap: one can work conscientiously, study, meditate and serve. Their differences chiefly concern orientation and spiritual aims.