Invoice is the proof of payment in a transaction involving the sale of goods, provision of labour service, or other business activities. It is also a document supporting that a payment and receipt has taken place, an official document for financial management and accounting, and an important tool in auditing for taxation purpose.
Invoices are generally in triplicate copies, namely the stub, invoice copy and accounts copy. Value-added tax (VAT) invoices have one more copy, which is the deduction copy.
