easy to package, and can be mailed at book rates. He additionally discounted books SO that they were often less costly than those at brick-and-mortar stores. Bezos recognized that in order to have a large market presence, he would have to offer low prices. He did this for many years, often operating at a loss or at low profit margins. The success of Amazon's book sales, whose prices undercut brick-and-mortar retailers, resulted in Barnes & Noble closing a number of stores, and Borders going out of business. To prop up sales, Barnes & Noble branched out into toys, games, and music. Many small, independent book stores went out of business because they were unable to match Amazon's prices. When they first sold merchandise online, Amazon did not charge the 5 percent to 7 percent sales tax on consumers' purchases charged in most states' retail stores. This put brick-and-mortar stores at a price www.TechnicalPDF.com disadvantage. States objected because it meant a loss in tax revenue. This changed, and Amazon now charges sales tax on all purchases. An innovation at Amazon was the introduction of customer reviews about products they had purchased. Amazon published both positive and negative product reviews. This is an important feature for online customers that cannot see products in person. Reviews are now a standard feature at many online retailers' sites. Amazon is the largest online retailer in the United States, about the same size as Chinese online retailer Alibaba. In addition, Amazon has a retail cloud presence in 14 countries outside of the United States. Amazon's success is aided by its fast shipping, free returns, and the breadth of its offerings. Amazon also offers streaming TV, which is free to Amazon's Prime customers that pay $119 annually for free deliveries and returns on Prime goods. In 2018, Amazon modified its prices for streaming and now offers streaming to non-Amazon Prime customers for a flat fee of $9 per month. It also hosts Marketplace, a service where other retailers list their products on Ama