In 1995, Amazon sold its first book from Jeff Bezos' garage. By 2006, Amazon had expanded globally and sold a variety of products from over 21 warehouses worldwide. Amazon uses Linux databases and Oracle software to power its large central data warehouse. While starting as an online bookseller, Amazon has branched out into various product categories and third-party sales, which now represent around 25% of its revenue. Amazon's goal is to be the most customer-centric company where people can find and buy anything online. It promotes itself in a cost-efficient way through associates who link to Amazon products from their own websites.