When an unlawful act is committed , it is called Malfeasance . The unlawful acts of Malfeasance are those which are generally actionable per se and do not require proof of damage or negligence or malice .
As for instance trespass is malfeasance and it is actionable per se .
When the act itself is lawful but performed improperly , it is called Misfeasance .A person becomes liable in tort even if he has undertaken to do something gratuitously and performs the work improperly or commits a misfeasance .
Failure or omission to perform an obligatory act by one is Non- feasance. But in case of Non- feasance , a gratuitous undertaking does not impose liability . Where there is an obligatory duty , and the failure or omission to do such duty causes injury to a person , it gives rise to a cause of action in favour of such person towards whom the duty exists .