Google Labs is a great place to test out new technology without risking integrating it into the main services before it is proven. Every once in a while though a technology is popular and mature enough that it gets promoted and introduced to the proper product. One interesting feature revealed last spring, when Google Labs was relaunched, was Similar Images for Google Image Search. As the name would imply, it enabled users to easily find images that shared similar traits, something that proved very useful in several cases, and the feature is now being introduced to the main Image Search site.

“Today, we're happy to announce that Similar Images is graduating from Google Labs and becoming a permanent feature in Google Images. You can try it out by clicking on "Find similar images" below the most popular images in our search results. For example, if you search for jaguar, you can use the "Find similar images" link to find more pictures of the car or the animal,” Google software engineers Erik Murphy-Chutorian and Chuck Rosenberg wrote.

In fact, Similar Images is the first major technology to graduate from Google Labs since the relaunch and it serves as a great example of how useful Labs can be. Using Similar Images is easy enough, and it doesn't require any additional steps from the user. Whenever you do an image search, some of the most popular results will have a “Find similar images” link under them. Clicking on it will refine the search to include only images that Google has determined are tied to the original one, being a similar subject or concept or just looking very much alike.

Google uses an image recognition technology to determine which images are alike but the results can vary. Further clicking on the “Find similar images” will refine the search once or twice but after that the results will stay the same. Still, for its most common use, differentiating between homonyms, it does its job very well. The feature is gradually being rolled out but it shouldn't be very long until it is available for all users.