Transactions (business transactions) are a business’s economic events recorded by accountants. Transactions may be external or internal.
External transactions involve economic events between the company and some outside enterprise. For example, Campus Pizza’s purchase of cooking equipment form a supplier, payment of monthly rent to the landlord, and sale of pizzas to customers are external transactions.
Internal transactions are economic events that occur entirely within one company. The use of cooking and cleaning supplies are internal transactions for Campus Pizza.
Transaction refers action in a bank account. Could be a deposit, withdrawal, debit card payment, service charge or interest payment.