Lists

The list is a simple data structure widely used in non-numeric programming.
A list is a sequence of any number of items, such as ann, tennis, tom, skiing. Such a list can be written in Prolog as:
[ann,tennis,tom,skiing]
Lists can be empty or non-empty. Empty list is shown as [] atom. Non-empty list can be viewed as consisting of two things:
The first item called head,
The remaining part called tail.