Containment Relationships

Uses

No ownership between classes, and they have their own lifetimes

Aggregation

If the parent class is deleted, the child class still exists

Composition

A 'death relationship'.
If the parent dies, the child dies (welp)

Inheritance Relationships

Is-A

An "is a" relationship functions by extending a class to produce another.

e.g. "A circle is a shape"

Has-A

A "has a" relationship functions by containing an object of a class within another class.

e.g. "A room has a chair"