The difference between an attribute and a value set.

An attribute is a property that describes an real world entity. Now for all entities there are certain values that each attribute can take. Set of all values that an attribute can take is called value set. Often the value that attribute take are lesser in number than number of element in value set. Difference between an attribute and value set can simply be taken as that between a variable and group of values that this variable can take. For example for a person an attribute can be name. For value of this attribute we can have any combination of character string so that will be the domain but in reality not all combination of characters exist as name of person.