Both decision and determination are related to the mental process whereby one chooses one way of doing something.
Decision is used in everyday language for the above process. In the law, decision is an official action taken by a person or a public agency on a specific legal or administrative issue.
Determination is a sub-element in a decision-making process, necessary to be made to resolve the entire set of issues. It is used in a contract situation when one or both parties choose a way of doing something as opposed to another.
