Classifier Role :- It classifies a role.
Association Role :- It shows relation between two classifier roles.
Multi-Object :- It used to show operation related to entire set of objects rather than on a single object.
Constraint :- Condition’s which must be maintained as true in order that system is valid.
2-Element Constraint: - It shows a constraint on two classes or associations.
OR constraint: - It shows an OR constraint on two classes or associations.