To help feed its insatiable hunger for information, Google has begun publicly testing Google Base, a service designed to host and make searchable "all types of online and offline content".

Described as an extension of the California company's existing content collection efforts, such as web crawl, Base can be used by large firms and individuals alike to post data in the form of categorised items that will be hosted and made searchable for free. So wrote Bindu Reddy, a company product manager, in Google's official weblog on Wednesday.

"This beta version of Google Base is another small step toward our goal: creating an online database of easily searchable, structured information," Reddy wrote.

People who post items to Base are asked to classify them with keywords or phrases, which Google calls labels, and to describe them with terms, which the firm calls attributes.

In this way, it appears to have made its most concrete move to date into the realm of user-generated content and tagging, popularised by services such as the social-bookmarking site and Yahoo's Flickr photo-sharing site.

The range of items that can be posted on Base is broad, encompassing such disparate things as poems, events, recipes, research papers, products and job postings, according to information on the Google Base website.

In addition to appearing on Google Base, items posted there could also surface in the company's main web index, the Froogle comparison shopping site and the Google Local listing of businesses.

In fact, Base will not be promoted as a service for information searchers, since the plan is to make the data appear in Google's various search services, said Salar Kamangar, vice-president of product management at the company, in an interview.

"Our primary goal with Google Base is to extend the ways we have of collecting content to make more information available to searchers," Kamangar said. "This is intended as an information store for other Google properties."

The Base search service is intended primarily for those who feed content to it, so they can see how their results appear and experiment with labels and attributes, he added.

"We're not driving [search] users to Base," he said. "This content will be searchable in some way from other Google properties."

For example, if an item is being posted for sale, it will appear in Froogle searches, and if it is a business listing, it will appear in Google Local. In a matter of weeks, Google's general web search will begin delivering Base results that are appropriate to that service, Kamangar said.

The service isn't built to be specifically an online classified-ads offering, as was rumoured when news of Base first surfaced in late October. "We could have done many things differently if that had been the intent," he said.

Those rumours returned last week when a patent application for a system called Google Automat was made public. Automat, it appears, is intended to help individuals advertise products and services online.

Google has historically relied heavily on pulling information from websites to index it, but it is increasing the ways it offers for users to push information over to the company, Kamangar said. One such service is Google Video, to which users upload their videos to have them indexed and hosted. But Base is open to a wider variety of information. "It's a more general way for people to push information to us," Kamangar added.

Individuals and companies whose sites and information are already indexed by Google probably don't need to re-enter that information in Base, unless they want to take the opportunity to more granularly label and categorise their data, he said.

The new service should be very attractive for individuals and companies that want to provide information that Google hasn't yet indexed, either because the information isn't online, or because it's online but technically difficult or impossible to index.

To facilitate matters, Base can create a web page to host information items, if the owner of the information doesn't have a site to post it to. Likewise, Base will also accept links to external websites where information resides, Kamangar said.

Current users of Google Base include and

Although Base is billed as a repository for "all types of online and offline content", some things can't be posted, including items that promote violence and offers of illegal drugs, fake documents, prostitution and other illegal activities.

A full description of Google Base guidelines and editorial policies can be found here.