Classic Line Item Display
You should only use the classic (old) line item display if you use it as a modification solution, that is, if you have modified it to meet your requirements.
For the classic line item display, you have to make various settings in Customizing. These settings are in Customizing for Financial Accounting under: General Ledger Accounting/Accounts Receivable and Accounts Payable → G/L Accounts/Customer Accounts/Vendor Accounts → Line Items → Display Line Items (without ALV).
You have the following options in the classic line item display:
For example, an accounts receivable clerk responsible for dunning requires dunning information in the line item display. This clerk requires a line layout with the relevant information. A credit controller requires summarized information. He will therefore display the information he requires using a