Inventory is the advertising space of a publisher.
The inventory define all the available ad spaces across a site.v
Ad units have a “parent-child” relationship, meaning that ads targeting the top-level ad unit (the parent) can also target the lower-level ad units (the children).
The hierarchy should mirror the organization of the site’s content.
- Sport (Parent)
- Tennis (Children)
- Football (Children)
- Baseball (Children)
A ad for sport can be shown on the children