If you are new in using accounting applications, here are some terms and description that can help you identify the forms in QuickBooks Online.
For more information in creating these forms, signed in your QuickBooks Online, select the Help (?) icon in the upper right.
An invoice is a bill for an account between a customer (buyer) and a supplier (supplier) indicating what was sold and how much is owed. These are sent when your customers are not paying immediately for goods/services sold and you are expecting a payment at a later date.
Receive Payment is used in conjunction with Invoice. When a customer is paying an invoice, you can record receiving the payment.
An estimate (quote) is created when you want to give your customer an estimation of how much a job will cost. The estimate (quote) form looks very much like an invoice, but its purpose is to help you begin negotiations with your customer. Later, once the estimate (quote) is accepted and you're ready to bill your customer, you can add data from the estimate (quote) onto an invoice.
Sales receipts are generally used for goods/services rendered at the time of a purchase (sometimes referred to as a "point of sale" purchase), or when customers give you immediate payment.
The status of the customer's account at a particular point in time. It represents sales transactions, credits, and payments in each line item for a given period. It doesn't offer as much detail as the individual sales transactions. It notifies your customers where they stand and if they still owe you any money. You send it to your customers on a regular basis.
A term used to describe transactions that are owed to suppliers/suppliers. It is an invoice your suppliers/suppliers send to collect money from you. Since you are a customer of the supplier/supplier, you would enter the invoice as a "bill" you are expected to pay.
Pay Bills is used in conjunction with Bill. When you are paying a supplier/supplier bill or multiple bills, you can record the bill payment.