Here's why:
* Ledger: A ledger is a primary book of account that contains a record of each financial transaction in a separate account. It's like a collection of individual account statements.
* Journal: A journal is where transactions are first recorded chronologically. It's like a diary of financial activity.
* Trial balance: A trial balance is a summary of all the debit and credit balances in the ledger at a specific point in time.
So, the ledger is the book that keeps individual accounts separated and updated.