Note: 'EAN' has been replaced with 'Barcode'
The product SKU (Stock Keeping Unit) code is a unique identifier of the product. It is the code by which products are stored and moved in and out of inventory locations.
A SKU code cannot be the same as an existing SKU code
A SKU code cannot be the same as a deleted SKU code
The SKU code of a Product cannot be updated if one of the following two conditions apply:
The product is included in one or more documents
The product is included in one or more bills of materials (only applies if the Production module is enabled).
The SKU code field can accommodate up to 20 characters
The EAN (European Article Number) code is an extra code that can be used to store the barcode information of the product. When the graphical representation of the EAN code is scanned with a scanner device, the system searches through the list of EAN codes in the database and fetches the Product to be included in documents without using a keyboard device. For example, a product can be automatically added to a purchase order using a Barcode Scanner.
The EAN field can accommodate up to 20 characters
Note the Serial Number is a different concept from the above - and it is used to identify specific items belonging to a particular product code.
Differentiating SKUs/product codes, barcodes and serial numbers
SKUs or Product Codes can be any combination of letters and numbers e.g. "iPhone-XS-32GB-Gold-1234". They are potentially readable both by people and machines.
Barcodes are typically comprised of numbers and can be represented also in images (the typical series of bars or QR codes). They are meant to be readable by machines (such as barcode scanners).
Serial numbers can also be either letters and numbers or numbers only and are meant to be processed by machines primarily. The key difference from the above two is that they are used to identify specific items of a specific product code. So out of the 10 units of "iPhone-XS-32GB-Gold-1234" in stock one may have a serial number of '990000862471854' and another '990000862471855'. This is useful to ensure returns refer to the same products, to track components used in production, etc.