Nutch is a nascent effort to implement an open-source web search engine.
Web search is a basic requirement for internet navigation, yet the number of web search engines is decreasing. Today's oligopoly could soon be a monopoly, with a single company controlling nearly all web search for its commercial gain. That would not be good for users of the internet.
Nutch provides a transparent alternative to commercial web search engines. Only open source search results can be fully trusted to be without bias. (Or at least their bias is public.) All existing major search engines have proprietary ranking formulas, and will not explain why a given page ranks as it does. Additionally, some search engines determine which sites to index based on payments, rather than on the merits of the sites themselves. Nutch, on the other hand, has nothing to hide and no motive to bias its results or its crawler in any way other than to try to give each user the best results possible.