Hi,
I have been searching for the difference between aggregation and composition and this is the best definition I could find.
Aggregation - Creates instance of another Class but has no relationship with this instance.
Composition - creates object within a class and the resulting object instance can be used to find the parent class that created it, i.e. the original class that created the object.
What I’m trying to figure out is would aggregation and composition be used on an uml conceptual class model since they seem very implementation specific?
Please forgive me as I’m a beginner to UML notation and using version 1.4.
Thanks. 
Hi marktheman,
Thank you for your post. In fact, the use of aggregation and composition depends on your design and how you would like to express your design.
If you have any inquiries, please feel free to ask.
Best regards,
Lilian Wong
