What you are speaking of is a vegetarian. there is a difference between a vegan and a vegetarian. Vegans eat only plant matter and do not intake any meat or meat products. A vegetarian on the other hand will often times eat eggs or milk which is a product of meat but they will not eat the actual meat of an animal. I have actually met a vegetarian that would not eat things such as pork, chicken or beef however would eat fish and shellfish. Some people decide to not eat meat based on their religion, personal preference or dietary restrictions.