1. A method to answer a query, comprising: saving, in a first database, website classifications of websites based on contents; receiving keywords; determining specifications of the query from the keywords; determining a group of websites that may own an answer to the query based on the query specifications and the website classifications saved in the first database; selecting a website from the group based on credibility of the websites saved in a second database; searching web pages of the website for the answer; selecting the answer from the web pages; and transmitting the answer.