What is an item number?

A wholesaler sells thousands of articles. A description such as "stainless bolt" could mean anything. With a code it is one specific article, with one price, one stock level and one supplier.

The code runs through the whole business: in the quotation, on the delivery note, in the price list, in purchasing and on the invoice. If each department has its own way of naming things, someone has to keep translating, and sooner or later it goes wrong. One code that everyone uses prevents that.

What goes wrong? The same product exists twice under two codes, so stock is scattered and nobody sees the real position. Or a code is reused for a different product, and old orders and reports suddenly no longer add up. Loose spreadsheets with their own codes cause confusion as well.

Think about the structure beforehand. Codes with a lot of meaning built in, such as the supplier or the size, look handy but become awkward when something changes. A short, fixed code with the properties stored separately stays manageable. Never use a code twice, even after an article has been discontinued.

The code is yours; the EAN code comes from outside and identifies the same product at suppliers and customers. When you move to a new system, the item number is often the key everything hangs on, so it pays to clean the list first, certainly in a data migration.

Finally, agree who creates new codes. If everyone may do it, the list grows with duplicates and unclear descriptions.