- IEnumerable is an interface that provides an Enumerator used to iterate over a collection that implements the IEnumerable.
- List is a concrete class that implements the IEnumerable interface for iteration and adds own set of methods for adding, removing and other operations on a list of items. It is a Generic type that can store a collection of any passed type.

Difference between IEnumerable and a List?
- IEnumerable is an interface that provides an Enumerator used to iterate over a collection that implements the IEnumerable.
- List is a concrete class that implements the IEnumerable interface for iteration and adds own set of methods for adding, removing and other operations on a list of items. It is a Generic type that can store a collection of any passed type.