When Google was launched in 1998 it was not the first search engine but it brought about a revolutionary change to the way search engines delivered results and how search engines looked. Today almost every major search engine delivers results in about the same way and by the same technique which is to simply enter a search term and click the search button and get a result.
While this technique has gotten us to this point the internet is now so mainstream and devices that access it are not all desktop computers so the need to change the way we search is growing as well.
I do not have a PHD in computer science and don’t pretend to know how everything works but it does make sense to me that search will evolve to include speech, eyesight, and probably smell as well. Add to that the ability to not just answer questions but be proactive and provide suggestions or data that is helpful depending on the time of day or task at hand and you might have a vision of the search engine of tomorrow.
Again I am by no means a search engine wizard but this post does a good job of giving insight into the future of search engines and it references Stefan Weitz and his new book Search: How the Data Explosion Makes us Smarter and he is a genius when it comes to search engines.