Acceptance under Indian contract act 1872?

the acceptance is the assent given to a proposal and it has the effect of converting the proposal into promise!!!

section2(b) of Indian contract Act defines Accptance as follows,

''when the person to whom the proposal is made signifies his assent therto,the proposal is said to be accepted.Aproposal,when accepted,becomes a promise.''

Essentials of a valid Acceptance,

1) it suld b fobbiden by law