Instant Pages preloads in Google back-end systems the results Google determines a user is most likely to click on. Webmasters tracking usage of their websites will see the difference between a page that Google preloaded from their site and wasn't clicked on, and pages that are actually visited by users, officials said.

In its initial implementation, Instant Pages will preload the page that ranks first on the search results list. Instant Pages will become available with the next beta release of Chrome, which includes a pre-rendering capability.

Instant Pages will also be offered for mobile devices in the coming weeks.

Google also announced that voice search and search by image, two features available for mobile devices, will now be available for desktop browsers as well.

Voice search, in which users speak their query terms, is being rolled out to Chrome desktop browser users, who will see a microphone icon in Google's search box.