Amazon is no longer a company that just sell books online.  It has grown and it is expanding into the web hosting and storage service.  Amazon S3 is the name, and helping people store file based on the amount of usage is the game.  The way of allow clients to buy a service online and pay only for what the use is called Cloud Computing. This keyword will be associated with Amazon from now on. Amazon S3 provides unlimited storage through a simple web services interface. Amazon launched S3, its first publicly-available web service, in the United States in March 2006. It stands for Simple Storage Service. S3 uses include web hosting, image hosting, and a back-up system. S3 comes with a 99.9% monthly uptime guarantee.