also known as object tree
Component this is the main abstract class for leaves.
Leaf creating leaves like creating the base objects. think about the company which is basically created by human beings overrides an abstract method from component
Composite composite is created by leaves. Department is also a composite as it contains several employee
think about the gift box example
component => giftbase leaf => toy composite => toy box (can contain several toys)
final gift can contain also several toy box but to calculate overall cost you will depend on toy costs