In accounting, each journal entry is like a set of instructions. Carrying out of these instructions is known as posting, a procedure that takes information recorded via journal entries (or journalizing) in the General or Special Journals and transfers it to the General Ledger. Each individual journal entry directs the input of a certain dollar amount as a debit in a specific ledger account, and directs the input of a certain dollar amount as a credit in a specific ledger account. Posting is always from the journal to the ledger accounts, and can be done two ways: the journal entries can be posted at the time the transaction is journalized; or the posting can be done at a set time like the end of the day, week, or month. Journal entries may also be posted as the journal page is filled if using a manual accounting system as a matter of personal taste. When posting the general journal, the date used in the ledger accounts is the date the transaction was recorded in the journal, not the date the journal entry was posted to the ledger accounts.
Since accountants and bookkeepers often need to trace the origin of a ledger entry, they use cross-indexing. In cross-indexing a notation is made for each entry that indicates which general or special journal account the general ledger entry came from. This practice makes it easy to trace an entry back to the original transaction. The account number appears in the Posting Reference column of the General Journal.
Continuing with our yoga studio example, posting journalized entires into T-accounts, and subsequently into the General Ledger, would look something like this: