What is an act of omission or commission?

Omission is not performing an act that is usually done or expected to be performed by a 'normal' person. LIke stopping at a scene of a traffic accident if you are a medical professional to assist, or not stopping if you are the first person, which is a crime. Commission is performing an act that results in some harm. Like, giving too much of a medication or too much oxgen or any other act that another. Think of it as omit vs commit. Unfortunately, from a legal standpoint, one is more liable of omission. Doing something unless it is blatantly wrong is not as liable.