A business source document is a legal paper that acts as proof that a particular transaction took place. Information contained on the business document may include Name of the business, name of the document, quantity, description, amount and terms if any. The following are some of the commonly used business documents.
- Invoice
- debit note
- credit note
- receipts, cash slips, banking slips, and cheque stabs
- petty cash voucher
- INVOICE
An invoice is a bill for goods bought or sold on credit. An invoice is produced when a transaction is done on credit. For example when a customer or a firm buys goods on credit, they will be availed with a bill known as an invoice.
Types of invoices
There are two main types of invoices; original and duplicate invoices.
An original invoice is given to the person or the customer buying goods on credit. It is a bill for goods bought on credit (credit Purchases).
A duplicate invoice remains in the invoice book after the original copy is given out. This copy shows the sales on credit by the firm. It is a copy showing the amount of goods sold on credit by the firm to its customer.

On the invoice there are letters E&OE written thereon which stand for errors and omissions excepted . This phrases means that mistakes are expected on the invoice and therefore corrections can be made. Here is a sample of an invoice.