Difference between an Entity and a Relation I am currently reading about entities and relations and I can't understand the difference between them? According to Wikipedia we have an example of a relation like in the pic:



This looks exactly like an entity set. What's the difference between an entity and a relation?
"Entity" is a real world concept, such as "a person" in your example. 

"Relation" is a set of tuples (records), each representing a model of an entity. In your example each tuple represents attributes of a single person, and their collection is a relation.