Below entire message below is a quote from DISA (Data Interchange Standards Association, INC.) and NOT my own words. But I believe this is the answer you are looking for.
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857 Shipment and Billing Notice
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This Draft Standard for Trial Use contains the format and establishes the data contents of the
Shipment and Billing Notice Transaction Set (857) for use within the context of an Electronic Data
Interchange (EDI) environment. This transaction set provides the recipient of a shipment with data for
both receipt planning and payment generation.
EDI and telecommunications technologies suggest efficiencies in the way business data is
processed. For example, the sender of a shipment may send the recipient’s receiving function a Ship
Notice/Manifest (856), and the payables function an Invoice (810), even though the contents of these
two documents may be largely redundant. In certain business environments, the Shipment and Billing
Notice permits the consolidation of these two documents into one.
Specifically, this transaction set is appropriate where the shipment data, when it includes terms and
item prices, can be used both to plan receipts and to generate payment. In this environment, the
exact prices for the items shipped may not be known in advance by both parties. This transaction set
is not appropriate in so-called Evaluated Receipts Settlement (ERS) environments, in which the exact
prices for the items shipped have been agreed upon by, and are known to, both parties in advance.
This transaction set is not to be used to replace the Ship Notice/Manifest (856) or Invoice (810)
individually, but only to replace both, together. For example, do not use this transaction set in place of
a Ship Notice/Manifest while continuing to send either paper or electronic invoice.