Basically there are two method of accounting:
1) Singal entry system
2) Double entry system

The first entry system does not use in modren time period.At the heart of modern financial accounting is the double-entry bookkeeping system. This system involves making at least two entries for every transaction: a debit in one account, and a corresponding credit in another account. The sum of all debits should always equal the sum of all credits, providing a simple way to check for errors. This system was first used in medieval Europe, although claims have been made that the system dates back to Ancient Rome or Greece.