Here is an example of what my idea for an Inventory-System with aera2D-Slot-detection.
In this case, when the OBJECT is moving with the MouseCursor over the Inventory-Slots, it will check if every OBJECT.area2D is over an INVENTORY-SLOT.area2D.
Only when all OBJECT.area2D signals detect a free INVENTORY-SLOT.area2D I can drop the object.
For me, this is the simplest way to build complex OBJECTS with different slot arrangements using the same simple Area-Signal-detection-code
So, that's why I used areas2D for this.
