Wolfram Alpha

Wolfram Alpha is a searcher of answers, not a search engine, developed by Wolfram Research.

This device answers directly the questions made, extracting the answer from a database, not given a list of websites or articles like Googles does. It is operative since 15th of May of 2009.

Since February of 2012, there is a Wolfram Alpha Pro service, which has special and advances functions, but it has a mensual cost for users.

www.WolframAlpha.com