In the last column, we talked about Cash, Receivables and Payables transactions. Early in your business, these transactions can just be recorded in a General Journal. Essential data is date, acct/amt acct/amt ..., and comments (e.g., who did you pay or who paid you).

In the old days (i.e., before computers), the General Journal was just a sheaf of columnar accounting paper where your most-used accounts had their own columns and the last column contained the rest (in acct/amt format).

At the end of each accounting period (e.g., at month-end), you'd take a calculator and total the amounts for each account and check that the account-totals totaled to zero -- which they never did -- whereupon you'd have to go back, find the transactions that didn't total to zero, correct them, and re-total the whole thing until they did come to zero. (You'd have to do this even if they totaled to only a penny -- because that penny could have resulted from two large errors whose difference was a penny.)

General Ledger

After verifying that the account-totals for the period in fact totaled to zero, you'd then "post" (i.e., copy) the account-totals to a General Ledger -- which was just another sheaf of columnar accounting paper, one sheet per account number, from which you could then compile your Balance Sheet and Earnings Statement. (Of course, after posting the General Ledger, you'd have to again total all the amounts you just posted, checking that they still totaled to zero, so you'd know you'd copied them correctly.)

As your business grows, just recording everything in the General Journal can get unwieldy.

Customer Ledger

You now have dozens of customers with dozens of transactions with each of them. The question is no longer "how much do they owe you", but "who owes you how much". So instead of recording customer transactions in the General Journal, you set up a Sales Journal (to record all invoices going to customers) and a Cash Receipts Journal (to record payments received from those customers).

At the end of each accounting period, you total the amounts for each account in these journals, and post them to the General Ledger (adding now a notation of what journal they came from) -- but you also post them to a Receivables Ledger (one sheet per customer) so you have a ready reference of how much each customer currently owes you.

Vendor Ledger

And you now have dozens of vendors with dozens of transactions with each of them. And the question is no longer "how much do I owe them", but "who do I owe how much to". So instead of recording vendor transactions in the General Journal, you set up a Purchase Journal (to record all invoices received from vendors) and a Purchase Disbursements Journal (to record all payments to those vendors).

And at the end of each accounting period, you total the amounts for each account in these journals, and post them to the General Ledger -- but you also post them to a Payables Ledger (one sheet per vendor) so you have a ready reference of how much you currently owe each vendor.

Employee Ledger

And you may now have dozens of employees with dozens of transactions with each of them. And the question is no longer "how much do I owe in payroll and payroll taxes", but "who do I owe how much to". So instead of recording employee transactions in the General Journal, you set up a Payroll Journal (to record all pay accrued by employees and all payroll taxes owed thereon) and a Payroll Disbursements Journal (to record all payments to those employees and the government).

And at the end of each accounting period, you total the amounts for each account in these journals, and post them to the General Ledger -- but you also post them to a Payroll Ledger (one sheet per employee) so you have a ready reference of how much you currently owe each employee and each government entity.

Other Ledgers

And you might add other Journals and other subsidiary Ledgers (e.g., Employee Advances, Employee Vacation, etc.) depending on the extent to which you need ready reference to their constituent balances. Candidates for subsidiary Ledgers are any asset, liability or equity accounts that you want to regularly break out by the entities (customers, vendors, employees, stockholders, etc.) that comprise their balance.

All the transactions in all these Journals needed to be totaled to zero (to be certain you had recorded them correctly) and when they are posted to the Ledgers, they needed to be totaled again (to be sure you transferred them correctly).