How do mudras that we make in our palm in yoga work ?

Looking out for information about working of palm mudras? Check out responses from experts on this here.

How mudras that we do in yoga works.
Is it real? Will any energy created while we do specific mudras? Which mudra is best to remove negative energy from the body?
I have heard of ksepana mudra. Other than this mudra is there any other mudra to remove negative energies from the body?