Black Web 2.0
Google Announces Instant Search
Sep 8, 2010 Aug 20, 2013

During their search event today, Google launched a few extremely important features they say will save you a lot of time when it comes to searching for what you want. Not only do you get results faster than before, but Google almost seems to read your mind as you type your search queries. It's called Google Instant. No more clicking to search. Just type.
Instant Search
Google Instant Search is a simple concept to understand, but brings tremendous power to the user. Rather than typing in a search query, pressing Enter, and waiting for you results, you get the results instantly. As you type your query, the search page updates dynamically to bring you the most relevant results.
Predictions
We've all had a lot of fun with Google's search predictions. As you type your search, Google tries to figure out what you are going to type. Predictions are show in gray and help you immediately refine your search. This is a lifesaver when you don't really know what you're searching for. For example, the title of a movie or name of a band.
Scroll To Search
This refers to the fact that you can scroll through Google's drop-down predictions and see the results of those queries instantly on the page. It's the cooperation between Instant Search and Predictions. Scrolling through your predictions and seeing the results immediately makes it that much quicker to find exactly what you want.
Feedback
Immediate feedback is what makes Google Instant so useful to you. As you type, Google suggests what you want. Not only will this save you some typing, but it may also help jog your memory about what you were really looking for or give you a suggestion for your next search.

Links and images show up on the page immediately via the magic of AJAX, which frees you up to continue your train of thought and finally get what you needed. How many times have you started out searching for one thing and got totally side-tracked somewhere else? Maybe you ended up doing so many searches that you even forgot what you were searching for.
The user benefits of Google Instant are many—but the primary one is time saved. Our testing has shown that Google Instant saves the average searcher two to five seconds per search. That may not seem like a lot at first, but it adds up. With Google Instant, we estimate that we’ll save our users 11 hours with each passing second!
Google Instant is rolling out now at Google.com for Chrome, Firefox, Safari and IE 8.

via Official Google Blog