Jnana yoga, also called gyana yoga, is the yoga of true knowledge. It is based on the Hindu philosophy 
nondualism, called advaita (nondual) vedanta (Vedic knowledge). A similar nondualistic view of reality is held by many branches of Buddhism, including Zen, by Taoism, by Islamic Sufism, as well as by some branches of Christianity that follow the Gospel of Thomas. Some of the best-known Hindu teachers of Jnana Yoga are Vashishtha, Adi Shankara, Ramana Maharshi, and Nisargadatta Maharaj.
Jnana yoga looks into the truth about who we are and what we are experiencing. The full realization of this truth brings enlightenment. Of course, all yogas offer a direct road to enlightenment if followed fully. Whether a particular road is suitable to reach this goal is a personal matter, largely depending on where you are coming from.
Jnana yoga can serve all people, whatever path they take. It keeps the true objective of yoga in sight and offers the blessing of truth getting closer at every step. But that does not make Jnana Yoga the only or even the best yogic path for everyone. Most yogis will combine jnana yoga with other yogic paths, such as bhakti yoga, karma yoga, ashtanga yoga and tantra yoga.
Jnana yoga is not based on any preliminary idea or dogma that you have to accept. It starts from direct experiences that anyone can have, even though these experiences may sometimes require deep contemplation and meditation.
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