The Sanskrit word Jnana means "knowledge".
What is knowledge ?
"knowledge of the true self".
Jnana Yoga is yoga of wisdom and knowledge. Jnana Yogis use an open, rational and curious mind in studying the spirit. Jnana Yoga is the Quest for the Self. In Jnana Yoga the intellect is used as a tool to know about our true Self. To realize about our true self , Jnana Yoga probes the nature of the Self through the question "Who am I?"
Jnana yoga teaches that there are four means to salvation:
Viveka - Discrimination:
The ability to differentiate between what is real/eternal and what is unreal/temporary. This discrimination springs from the intuitive conviction that the eternal and unchanging Brahman alone is real, and all other objects are transitory and unreal.
Vairagya - Dispassion:
This means non-attachment to all pleasures, ranging from the enjoyment of the tangible objects found on earth to that of the happiness a virtuous soul experiences in heaven. After practice one should be able to "detach" her/himself from everything that is "temporary."
Shad-sampat - The 6 Virtues as follows,
Tranquility (control of the mind),
Dama (control of the body and the senses),
Uparati (renunciation of activities that are not duties),
Samadhana (perfect concentration).
Mumukshutva - Intense longing for liberation from temporal limitations.
One of the philosophical fundamental pillars of Jnana yoga is nondualism which is a fundamental belief in the unity of the universe, especially of the individual soul atman with brahman or transcendent, all pervasive ultimate reality. The desire for liberation mentioned above might be described as "wanting to be one with the universe."