1. A structured list of items

Bills of materials (BOMs) are the solution to the management problems caused by the complexity of the assemblies to be designed and manufactured. It is a tool for organizing and codifying large volumes of information: indeed, it is not uncommon to count several thousand elements in the composition of industrial products.

To create a bill of materials, you need at least to identify the basic data (usually by number and designation), but also to classify and group them, and specify the conditions of use.

For this purpose, the nomenclature is organized around three main entities (figure 1 ):

• lastructure: a tree structure that allows grouping according to an easily understandable logic;