A beneficiary is a person or organization who will benefit and/or inherit from the distribution of your assets under your Will. Anyone can be named as your beneficiary, including your appointed executor except for animals, as Malaysian Law does not recognize animals as a legal beneficiary.
The difference between an heir and a beneficiary is that an heir is someone related to you by blood, and they might not be listed specifically in your Will as beneficiary, whereas a beneficiary is an individual specifically listed in your Will. This beneficiary can be your family member, friend, or organization.