Google Base: Google Base was a free database created and provided by Google. The database allowed users to add various types of content, including images, text and structured information in XML, PDF, Excel, RTF, and other formats. Google Base was used to help Google understand what types of information should be considered commercial, which could help determine how the search engine should structure different vertical search products. However, in 2010, Google Base was downgraded to the Google Merchant Center, which now allows merchants to upload their product feeds, making them easier to find through Google Product Search.
In many ways, Google Base was designed to act like an online classified service. Unlike websites like Craigslist, however, it was used for a wider range of products and information, including current events, protein structures, recipes, real estate, and more. This drew interest to the field of information technology and its role in modern technology even before Google Base was officially released, as details of the project were leaked before the service was launched.