What is Jnana yoga?

Jnana is Sanskrit for “knowledge or wisdom” and Jnana Yoga is the path of attaining knowledge of the true nature of reality through the practice of meditation, self-inquiry, and contemplation. Jnana Yoga can be defined as the “awareness of absolute consciousness,” and is a comprehensive practice of self-study (Svadhyaya).

In Jnana yoga, the mind is used to inquire into its own nature and to transcend the mind’s identification with its thoughts and ego. The fundamental goal of Jnana yoga is to become liberated from the illusionary world of maya (self-limiting thoughts and perceptions) and to achieve the union of the inner Self (Atman) with the oneness of all life (Brahman). This is achieved by steadfastly practicing the mental techniques of self-questioning, reflection and conscious illumination that are defined in the Four Pillars of Knowledge. Jnana Yoga utilizes a one-pointed meditation on a single question of self-inquiry to remove the veils of illusion created by your concepts, world views, and perceptions. This practice allows you to realize the temporary and illusionary nature of maya and to see the oneness of all things.

It's the path of knowledge. It's for intleggent people, who don't like physical action. It's for people who like to read, who like philosophy, who like academically study. But Bhakti and Karma is must too. Janana, Bhakti and Karma is 3 corners of one triangle, If for you east to start from knowledge part, do it. Karma and Bhakti will come later.

Jnana yoga is Self realisation (Atma Gnana).For example Adi Sankara charya is a Gnana Yogi.Great Pathnjali Maharshi in his Yoga Darshana says that by practice of astanga yoga the impurities of mind (Rajas  & Tamasic)removed and satva guna improves then Viveka Kyathi ( A special Gnana/knowledge) born and yogi experiences the knowledge of Atman which is eternal and the body,mind and intellect are part of nature subject to continuos change.Therefore Jnana Yoga is Knowledge part.Knowledge about Self/Soul,Supreme Soul(GOD),Nature/world and the relation between all these.In Shatdarshanas this Gnana was eloborated and Yoga darshana by Pathanjali is one of the Shat Darshanas( Six Dharshanas)