Last year Google was warning webmasters that search results were not welcome in their index.
Last week it started generating its own search results from websites by filling in html forms. What's going on?
According to Google, the Googlebot is able to follow web forms using both text box inputs and drop down or select boxes.
For select menus and radio buttons Google will choose values from the html and submit the form (it only does this with GET forms) to see if the results are something that might be helpful to searchers.
This strategy is quite straightforward and will help Google index a lot of the "invisible" web that exists behind these forms.
The interesting part of the new system is when Google fills in a search box on a site using a made up query.
Googlebot is able to generate queries that it thinks might be relevant to their users (or queries where they don't have many results at present) and enter these queries into a search box to try and find more results.
Essentially Google is automatically generating queries and performing those queries on internal search engines on millions of websites to see what it can find.
Webmasters are already spotting this and some are concerned about the content being indexed as well as increased server load.