Composition that is used to store several instances of the composited data type is referred to as containment. Examples of such containers are arrays, associative arrays, binary trees, and linked lists.
In UML, containment is depicted with a multiplicity of 1 or 0..n (depending on the issue of ownership), indicating that the data type is composed of an unknown number of instances of the composited data type.
In OOP supported languages, containership means an object is created within another object.
For Example in C++:
References
Containment (computer programming) Wikipedia(Text) CC BY-SA