Production 
Purpose
You use the SAP Business One Production module to define bills of materials (BOM) for your products, and to create and maintain production orders.
In the bill of materials for a quantity of finished product, you specify the various components that make up that product, and the appropriate quantities of the components. The information in the bill of materials is used for planning the appropriate quantities of the components.
Production Order is a command to produce or repair a production item. The Production Order supports the planning and assembly of a production item. It also tracks all the material transactions and costs that are involved in the production process, as well as additional costs such as labor overhead.
SAP Business One supports three Production Order types, Standard, Special, and Disassembly, improving the organization of your work. The Standard production order is used for regular production. Components are copied from the item Bill of Materials. The Special production order is used to produce items or to perform activities at the shop floor that are not based on the standard BOM. The Disassembly production order is used to report the disassembly of an item with a production BOM. Components are copied from the item Bill of Materials.
In some cases, a finished product is the result of an entire production process. In other cases, though, a finished product might simply be a collection of items that are sold as a unit but are not the output of a production or assembly process.
See also:
Update Parent Item Prices Globally