Jnana means wisdom or discernment. Jnana yoga is the path of wisdom and jnana meditation is many-faceted.
This is supposed to be the yoga of the intelligent or the superior few. All other varieties of yoga are believed ultimately to lead to this kind of yoga, in which one comes to look at everything in the world as it is, without any ignorance and bias. This is supposed to be achieved through a continued practice of a strenuous mental discipline and virtue. This variety is also called Raja Yoga, because it is the highest variety, so to say, or the yoga that presides. Perhaps it is the variety which patanjali has described in his Yoga Sutra. He has said that it is made of eight parts, five of which are said to be external, and three internal. Yama and Niyama, that is, the first two patts, are concerned respectively with what habits a student of yoga should avoid (e.g. harming others, speaking Jies, stealing, gathering wealth unnecessarily, etc.), and what habits he should positively cultivate (e.g. cleanliness of the body and mind, contentment, devotion etc.) Asana and Pranayama, which are respectively the third and fourth parts in patanjali’s system, are dealt with elaborately in Hatha Yoga.
The fifth part, namely, Pratyahara, indicates a withdrawal of the sense organs from the objects of enjoyment. The next three parts consist of a process of progressive mental concentration. Patanjali argues that through a faithful and intense practice of these eight parts of yoga for a sufficient length of time, a student of yoga can wash away all the impurities of his body and mind, so that he attains knowledge which ultimately liberates him from bondage and ignorance. This yoga is also called Ashtanga Yoga, because of the fact that it is made of eight parts. It is also sometimes called Dhyana Yoga, because of an emphasis on mental concentration. We find a lucid description of this variety of yoga in the sixth chapter of the Gita. It is usually this yoga that is implied whenever the word “yoga” stands alone without any qualification.