Hopefully one day they will be united into one standard that is accepted all over the world.
Every Year there is new EDI version that comes out and published by the parent organization which is ASC X12 and usually there are minor changes to existing documents and sometimes new documents, so if your going to pick an EDI solution, make sure that comply with all the previous version or at least all the version that you use + all the versions that your trading partner uses. Because most changes are minor, even if you use older version, your EDI software should be able to process the documents it was configured initially to process, but in some cases you might get error messages about invalid file format or invalid segment or invalid element.
EDI X12 file structure is made of four levels:

1. ISA - Interchange Segment
2. GS - Group Segment
3. ST - Segment Transaction
4. Transaction Segments for specific ST

So what we got here is a tree view that look like this:
        ISA
                GS
                        ST
                                G50
                                G72
                        SE
                GE
        ISE
ST has multiple segments
GS may have one or more Transactions
ISA may have one or more Group segments
ISA, IEA GS, GE ST and SE are being called Control Segments where all the segments inside the ST being called Data Segments.
Sample of EDI 810 document:
ISA*00* *00* *08*9251730000 *12*7142569388T *050215*1514*U*00401*000005132*0*P*>~
        GS*IN*2137279234*7142569388*040713*1514*000000001*X*004010UCS~
                ST*810*0001~
                        BIG*040713*1001*040625*P89320~
                        N1*BT*ACME DISTRIBUTING COMPANY~
                        N3*P.O. BOX 33327~
                        N4*ANYTOWN*NJ*44509~
                        N1*ST*THE CORNER STORE~
                        N3*601 FIRST STREET~
                        N4*CROSSROADS*MI*48106~
                        N1*RI*SMITH CORPORATION~
                        N3*900 EASY STREET~
                        N4*BIG CITY*NJ*15455~
                        PER*AD*C.P.JONES*TE*6185558230~
                        ITD*01*3*2**10~
                        IT1**3*CA*12.75**VC*6900~
                        IT1**12*EA*.475**VC*P450~
                        IT1**4*EA*.94**VC*1640Y~
                        IT1**1*DZ*3.4**VC*1507~
                        TDS*5111*~
                        CAD*M****CONSOLIDATED TRUCK~
                        CTT*4*20~
                SE*21*0001~
        GE*1*000000001~
IEA*1*000005132~

A closer look at one of the Data Segments:
BIG*040713*1001*040625*P89320~
Each part between the asterisk sign called Element and the asterisk separates the elements from each other. In other cases, there could be a different character that separates the Element from each other. The same goes for the ~ which is the Segment Terminator.
The ~ sign tells the EDI system when the segment ends.
The first tokens, BIG, tells the EDI what this segments is all about, in this case BIG tell the system that this is 'Beginning Segment Invoice'
The second token, 040713, is the Invoice date formatted as YYMMDD, which is Year Month and Day, so in this case the Invoice Date would be July 13 2004
The third token 1001, is the Invoice Number.
The fourth element 040625, the date assigned by the purchaser to purchase order.
The fifth element P89320, Purchase Order Number for that Invoice.
The BIG data segment has more elements, but not all of them must be used. The ASC X12 define specifically which element are mandatory and which are optional.

Page 2 of 2 :: First | Last :: Prev | 1 2 | Next