A receipt is a written acknowledgment that a specified article or payment has been received. A receipt records the sale of goods or provision of a service. If the recipient of the payment is required to collect a tax from the customer, the amount collected would also be included on the receipt and the amount would be deemed to have been collected on behalf of the relevant government tax authority. In many countries a retailer is required to include the tax and similar amounts in the price of goods sold. Similarly, amounts may be deducted from amounts payable, as in the case of wage withholding taxes. On the other hand, tips or other gratuities given by a customer, for example in a restaurant, would not form part of the payment amount. In some countries, it is obligatory for a business to provide a receipt to a customer confirming the details of a transaction. In most cases the recipient of money provides the receipt, but in some cases the receipt is generated by the payer, as in the case of goods returned to a store for a refund. A receipt is not the same as an invoice. However, there is usually no set form for a receipt, such as a requirement that it be machine generated. Many point-of-sale terminals or cash registers automatically produce receipts. Receipts may also be generated by accounting systems, be manually produced or generated electronically, for example if there is not a face-to-face transaction. To reduce the cost of postage and processing, many businesses do not mail receipts to customers, unless specifically requested or required by law; some transmitting them electronically. Others, to reduce time and paper, may endorse an invoice, account or statement as “Paid”.