Although dhyana mudra is most commonly used and known in Buddhism, it was known long before the Buddha as Hindu yogis have practiced it during their meditations.
This mudra represents the gesture of total balance. The person using this mudra during meditation is immersed in the limitless space, completely untouched by the outside world. The right hand symbolizes wisdom and awareness and the left one symbolizes the iillusion of existence.
It is believed that dhyana mudra was practiced by Sakyamuni during his meditation under the pipal tree before he achieved enlightenment. It can be usually seen in icons of the fourth Dhyani, Buddha Amitabha.
In Buddhism, the dhyana mudra is sometimes performed with one hand only where only the left hand is placed in the lap, representing the female principle of sense and wisdom.