A bill; a commercial document issued by a seller to a buyer indicating the products, quantities and agreed prices for products or services that the seller has already provided the buyer with. An invoice indicates that, unless paid in advance, payment is due by the buyer to the seller, according to the agreed terms.
发票，是指经济活动中，由出售方向购买方签发的文本，内容包括向购买者提供产品或服务的名称、品質、协议价格。