EDI Glossary

Acknowledgment

A general term for any transaction confirming receipt or processing of another document, ranging from technical (997) to business-level (855) acknowledgments.

AS2 (Applicability Statement 2)

A secure, internet-based protocol for transmitting EDI documents directly between trading partners, using digital certificates for encryption and signing, with MDN receipts confirming delivery.

ASN (Advance Ship Notice)

A shipment notification sent before or at the time of shipping, detailing what was shipped, how it was packed, and expected arrival — the business term for the X12 856 / EDIFACT DESADV.

BEG (Beginning Segment for Purchase Order)

The X12 850 segment that carries the purchase order number, type, and date, marking the start of the transaction's business content.

CARC (Claim Adjustment Reason Code)

A standardized code used in the X12 835 to explain why a claim payment differs from the amount billed.

Chargeback

A financial penalty assessed by a retailer against a supplier for failing to meet EDI or shipping compliance requirements, such as a late or inaccurate ASN.

Clearinghouse (Healthcare)

An intermediary that receives healthcare EDI transactions (837, 270, 276) from providers, validates and reformats them, and routes them to the correct payer.

EDI (Electronic Data Interchange)

The computer-to-computer exchange of business documents, such as purchase orders and invoices, in a standard electronic format between trading partners, without human intervention.

EDIFACT

UN/EDIFACT (United Nations EDI for Administration, Commerce and Transport) is the international EDI standard maintained by the UNECE, common in Europe and global trade.

Element

The smallest unit of data in an EDI segment, such as a quantity or a date, separated from other elements by a delimiter character.

Envelope

The set of control segments (ISA/GS/ST...SE/GE/IEA in X12, or UNB/UNH...UNT/UNZ in EDIFACT) that wrap one or more business documents for transmission.

Functional Acknowledgment

The X12 997 (or 999) transaction confirming an interchange was received and whether it passed structural validation, without judging business content.

GE (Functional Group Trailer)

Closes a functional group, containing a count of included transaction sets and the matching group control number from the GS.

GS (Functional Group Header)

Marks the start of a functional group — a batch of one or more transaction sets of the same type (e.g., all 850s) — within an X12 interchange.

HL (Hierarchical Level)

An X12 segment used to build parent-child relationships between loops, such as shipment, order, pack, and item levels in an 856 ASN.

IEA (Interchange Control Trailer)

The closing segment of an X12 interchange, containing a count of functional groups and the matching interchange control number from the ISA.

ISA (Interchange Control Header)

The first segment of an X12 interchange, identifying the sender, receiver, and control number for the entire envelope of transactions.

Loop

A repeating group of segments in an EDI transaction, such as the PO1 loop in an 850 (one per line item) or the HL loop in an 856 (one per hierarchical level).

Mapping

The process of defining how data fields in one format (an ERP record, a database table, a CSV file) correspond to segments and elements in an EDI standard, and vice versa.

MDN (Message Disposition Notification)

The receipt returned by an AS2 receiver confirming that a message was received, and whether it was successfully decrypted and verified.

N1 (Party Identification)

An X12 segment identifying a party involved in the transaction, such as a buyer, seller, ship-to, or bill-to location.

NPI (National Provider Identifier)

A unique 10-digit identification number for covered healthcare providers in the United States, used throughout HIPAA X12 transactions.

PO1 (Baseline Item Data)

The X12 850 segment representing a single line item on a purchase order, including quantity, unit price, and product identifiers.

Qualifier

A code element that defines how to interpret the data element that follows it, such as a reference qualifier or a quantity qualifier.

RARC (Remittance Advice Remark Code)

A standardized code providing additional explanatory detail alongside a CARC in an X12 835 remittance advice.

SE (Transaction Set Trailer)

Closes a transaction set, containing a count of included segments and the matching transaction set control number from the ST.

Segment

A line of related data elements in an EDI transaction, identified by a segment ID (e.g., BEG, N1, PO1) and terminated by a segment delimiter.

SFTP (SSH File Transfer Protocol)

A common file-transfer protocol used for EDI exchange, often as a mailbox-based alternative to AS2 when a VAN or direct connection isn't used.

SSCC (Serial Shipping Container Code)

An 18-digit GS1 identifier assigned to a logistics unit (pallet or carton) and printed as a barcode, linking the physical package to its electronic ASN record.

ST (Transaction Set Header)

Marks the beginning of a single X12 transaction set (e.g., one purchase order) and specifies its type code and control number.

TPA (Trading Partner Agreement)

A formal document defining the technical and business rules between two trading partners: which transaction sets are used, communication protocols, testing requirements, and SLAs.

Trading Partner

Any external business (customer, supplier, carrier, or bank) with whom an organization exchanges EDI documents.

Translation

The runtime process of converting data from one format to another according to a mapping specification — for example, converting an internal order record into an X12 850 file.

UNB (Interchange Header)

The EDIFACT segment that opens an interchange, identifying sender, recipient, and interchange control reference — the EDIFACT counterpart to X12's ISA.

UNH (Message Header)

The EDIFACT segment that begins an individual message (such as ORDERS or INVOIC) within an interchange — the EDIFACT counterpart to X12's ST.

VAN (Value-Added Network)

A third-party network that routes EDI documents between trading partners, historically over dial-up or private networks, now typically over the internet with mailbox services.

Vendor Compliance

A retailer's program of EDI, labeling, and shipping requirements that suppliers must meet, enforced through routing guides and chargebacks.

X12

ANSI ASC X12 is the American standards body and the EDI standard it maintains, widely used in North America for retail, logistics, finance, and healthcare transactions.