When the size of an organisation is very large and there are a number of accounts, it is not possible to keep all these accounts in a ledger. Generally, the following three kinds of ledgers are maintained by such organisation:
Debtors’ Ledger:
It contains the accounts of all the customers to whom goods have been sold on credit.

image source: 1.bp.blogspot.com/-Cy9wGu96Sxo/VHgr9zrDX1I/AAAAAAAAGHI/rQpCJR5deEc/s1600/how-to-create-debtor-ledger-account-in-tally-image.jpg
ADVERTISEMENTS:
Creditors’ Ledger:
It contains the accounts of all the suppliers from whom goods have been purchased on credit.
General Ledger:
It contains all other accounts except customer accounts and supplier accounts.