Accounting Symbols: The characters "Debit" and "Credit" are used as accounting symbols, representing the left and right sides of an account, respectively. Debit and Credit are purely bookkeeping symbols. They have become professional terms in accounting , used to indicate the direction of an entry. Whether "Debit" represents an increase or "Credit" represents an increase depends on the nature and structure of the account. Under the double-entry bookkeeping system, the economic content reflected by the debit and credit sides of different types of accounts varies.

1. Structure of Asset Accounts

Bookkeeping Rule: Debit increases, Credit decreases, balance is on the debit side.

Debit side ending balance = Debit side beginning balance + Debit side current period transactions – Credit side current period transactions

2. Structure of Liability Accounts

Bookkeeping Rule: Credit increases, Debit decreases, balance is on the credit side.

Credit side ending balance = Credit side beginning balance + Credit side current period transactions – Debit side current period transactions

3. Structure of Owner's Equity Accounts (Same as Liability Accounts)

Bookkeeping Rule: Credit increases, Debit decreases, balance is on the credit side.

Credit side ending balance = Credit side beginning balance + Credit side current period transactions – Debit side current period transactions

4. Income and Expense Accounts

(1) Bookkeeping Rule for Revenue Accounts: Credit increases, Debit decreases, no ending balance.

(2) Bookkeeping Rule for Expense Accounts: Debit increases, Credit decreases, no ending balance.

5. Cost Accounts

Bookkeeping Rule: Debit increases, Credit decreases, beginning and ending balances are on the debit side.

Double-entry bookkeeping refers to a method that uses the accounting equation as its principle and 'Debit' and 'Credit' as its symbols to reflect changes in economic transactions. With the development of the commodity economy, double-entry bookkeeping has been widely applied. The scope of recording is no longer limited to creditor and debtor relationships, but has expanded to include recording changes in assets and calculating operating profit and loss.

The bookkeeping rules of double-entry bookkeeping can be summarized as: For every debit, there must be a credit; debits must equal credits.

When using double-entry bookkeeping, for every economic transaction, an entry must be made to the debit side of one (or several) accounts, and necessarily to the credit side of another (or several) accounts, which means "for every debit, there must be a credit"; the amount recorded on the debit side of an account must equal the amount recorded on the credit side of an account, which means "debits must equal credits".