The primary benefit of user-defined fields, or UDFs, is that they allow you to easily extend your ERP database structure. With no customizations and very little configuration. You can add a UDF to a wide selection of tables in SAP B1 with a few clicks. This allows you to track specific information about business partners and demographics, or even documentation used in the sales process. The data stored in these fields is also extremely versatile, ranging from drop-downs and boolean to a string of characters or even a link. This provides many options when integrating with a web store.