What's the difference between the Create Receipt and Add to Receipt options when creating a receipt?

Select Create Receipt to create a new receipt for the lines. You can record the receipt number manually or let the application create a receipt number based on the value of the receipt number Generation parameter previously set up.

Select Add to Receipt to add receipt lines to an existing receipt number. You can select the receipt from a list of previously received receipts.

With both the Create Receipt and Add to Receipt options, you can update all attributes on the receipt header except for the supplier or customer. You can enter shipment-related information such as shipment, packing slip, shipping method, shipped date, waybill, and bill of lading.