My Favourite -- Dhyana Mudra

Dhyana Mudra→ Mediation Mudra

The Dhyana mudra ("meditation mudra") is the gesture of meditation or concentration (Sanskrit: samadhi mudra).

The Dhyana mudra may be made with one or both hands. When made with both hands, the hands are generally held at the level of the 

stomach or on the lap with the palms facing upwards, and the fingers extended.

* The right hand always rests upon the left hand. This symbolizes that the perfections of method (right hand) are supported by the 

perfection of wisdom (left hand). 


*In some cases the thumbs of the two hands may touch at the tips, thus forming a triangle
. 
*The esoteric sects obviously attribute to this triangle a multitude of meanings, the most important being the identification with the mystic fire that consumes all impurities. 
The joined thumbs do not form a "mystic triangle" and are placed against the palm.

It originated in India most likely long before the Buddha as yogis have used it during their concentration, healing, and meditation exercises. 

Dhyana mudra is also known as Samadhi mudra or Yoga mudra.