Set is a collection of things, called elements.
Notation defining a set:
Capital letters are used for set names, elements are separated with comma and ellipsis (…) is used:
- as a shortcut for listing many elements, when in the middle for finite sets
- to indicate a set goes on forever, when at the end for infinite sets
Notation for representing:
- An element belongs to a set:
- An element does not belong to a set: