Modern society is a product of society, we are of their own money, commodities trading has become very free, so every business marketing tool has become particularly important. For the business, not only depends on the sales price of merchandise can be profitable, need to look up whether to increase sales. There is a set sales should be able to increase sales, because the same one each time the consumer goods could only buy one, but you will be bundling a group of products, consumers will find the prices cheaper than a single sale to choose.