Bills of Material are used to define the various items that you build, or assemble in-house.
Each Bill of Materials consists of a Bill of Materials Header record (stored in the BOMHEAD file), and one or more Bill of Materials line item records (stored in the BOM file).
Each BOM header record contains information about the item number that is being built, a revision number, and a unique BOM number.
By creating multiple BOMs with different revision numbers, you can store multiple bills of materials for each item that can be built.
Each bill of materials is also assigned a unique BOM number. The BOM number is a unique number that is stored in both the BOMHEAD and BOM records, and it is used to attach comment and other information to the Bill of Material.
The revision number and the BOM number are automatically assigned to each Bill of Materials as it is created and these numbers are loaded into any line items that are added to the BOM. The revision number in the BOM is also carried into any Shop Orders that are created from the BOM, so you can identify the particular BOM revision that was used for a specific shop order.