Yoga means ‘union’ or ‘connection’. In Sanskrit, the word ‘yoga’ is used to signify any form of connection. Yoga is both a state of connection and a body of techniques that allow us to connect to anything.
Conscious connection to something allows us to feel and experience that thing, person, or experience. The experience of connection is a state of yoga, a joyful and blissful, fulfilling experience.
Awareness is the secret of yoga.
There are many traditional yogic paths that facilitate connection to the highest truth and awaken our own consciousness, including tantra, mantra, laya, kundalini, bhakti, jnana, karma yoga, and so on. Each path specializes in its own techniques and methods to awaken greater awareness and connection to self and life.
Yoga practices include posture (asana), breathing (pranayama), control of subtle forces (mudra and bandha), cleansing the body-mind (shat karma), visualizations, chanting of mantras, and many forms of meditation.
Yoga is a science, that is, it is a body of techniques that lead us to consciously connect with ourselves and with life, the experience of yoga. As yoga is a science, there is no dogma or belief system attached to it. Yoga simply tells us to do a certain practice and then to feel the effect of that practice, e.g. if we breath slowly in a relaxed manner we will slow our heart rate; if we focus the mind we will develop mental peace and deep insight.
In a philosophical sense, however, yoga means the conscious connection of the limited little egoic self with the unlimited, eternal, higher Self.