A beta version of the search engine Microsoft is developing went live Thursday, offering users an interface and set of features that make the product begin to resemble established search engines from competitors Google, Yahoo, Ask Jeeves and AOL.

A less developed version of the MSN Search service that Microsoft began making available for public tryouts in July, was simply a search box without special features or functionality that returned results grabbed from an index of about one billion documents, a Microsoft official said.

But the beta version released Thursday has an index of over five billion documents and lets users narrow and customize their queries in a variety of ways, said Justin Osmer, an MSN Search product manager.

The MSN Search service is expected to be ready in final release in 2005 and will eventually replace the search engine technology that Microsoft currently licenses from Yahoo to power the MSN portal's search feature, he said. "Our overall goal with this beta and eventually with the final product is to help users find whatever information they want faster," Osmer said.

Charlene Li, a Forrester Research Inc. analyst, has tested the search engine and described the relevance of its results as being "not fantastic" but definitely adequate and "on par" with its competitors.