In this transaction you are defining Leger Groups. They are necessary when you want to do postings. Usually, you will not choose a particular ledger, but instead a ledger group. You could assign one or several ledgers to particular ledger group which could help you to do parallel postings in the same time.
IMG Path: Financial Accounting (New) -> Financial Accounting Global Settings (New) -> Ledgers -> Ledger -> Define Ledger Group
Tables: FAGL_TLDGRP, FAGL_TLDGRPT, FAGL_TLDGRP_MAP
When you enter into the transaction you could edit the assignment of a particular group or to create a new group and assignments of ledgers.
If you choosed in previous step a custom ledger group you will see here a “New Entries” button to add other ledgers as well.