Your company has the ability to create custom fields to capture extra analysis data based on requirements.
These fields are then configured to work with certain layouts, which can be system default layouts, or layouts that you have created.
See Manage layouts for more information.
Reasons for having varying layouts exist and typically relate to the type of invoice requiring extra analysis data to be captured.
A CAPEX invoice (relating to capital expenditure) may require fixed asset codes and other depreciation related allocations, whereas, an OPEX invoice (operating expenditure) may not require these.
Therefore, your company could create a layout for OPEX invoices and a layout for CAPEX invoices, and using our events and actions system, decide when, and if to use either layout form.