Definition
The general ledger (GL) is the complete record of a business's accounts, holding every posted debit and credit and the running balance of each account.
What is a general ledger used for?
Journal entries are posted to the GL, and the GL is the source of the trial balance and financial statements. Sub-ledgers, such as receivables or inventory, hold the detail by customer or item and should agree with their control accounts in the GL. When they don’t, something was posted to one and not the other.
Example: the Accounts receivable control account shows USD 412,000, matching the total of open customer invoices in the receivables sub-ledger.
A good GL lets you drill from any balance to the documents behind it.