Shipping addresses differ in functionality and meaning depending on the context of the situation.
Origin Shipping Address
Shipping addresses saved on an account are used to originate a shipment, on Easyship you can add multiple origin ship-from addresses and set different conditions to use them. As a shipper, shipping addresses enable accurate calculation of shipping costs and can be used by couriers to pick up a shipment.
Destination Shipping Address
Destination addresses refer to the buyer's location and will be present on the shipping label. Such addresses can be entered manually or synced from a store when Creating Shipments.
A billing address is used for transactional purposes and is entered when adding payment information into a store or software.
You can save origin and billing addresses in the Account > Addresses section of the dashboard.