Collected here are a variety of search engines for searching the internet. Basic search engines try to search all the web, though each one succeeds in searching only a part of it. Metasearch engines run a search in many basic and specialized search engines and compile the results. Specialized search engines search a specific part of the internet or subset of the web.

To see useful links we've selected for learning about NASA or other topics, see our Browse topics and our bibliographies. If you are having trouble finding a NASA website, you can request assistance. Registered Library Patrons can also request assistance in any work-related web research and can request training in advanced internet searching techniques.

Basic Search Engines

AlltheWeb - Basic search engine based on Yahoo's index.

Alta Vista - Basic search engine. Includes a translation service.

Ask Jeeves - Basic search engine based on Teoma.

Go.com - Basic search engine. Disney site powered by Yahoo.

Google - Basic search engine. Includes specialized search engines and a translator.

Hotbot - Basic search engine with the usual advanced search capabilities.

Look Smart - Basic search engine that also has a searchable directory of selected links and an article database.

Lycos - Basic search engine. Suggests topics to narrow your search.

Teoma - Basic search engine. Suggests topics to narrow your search.

WiseNut - Basic search engine. Offers WiseGuide, which arranges your results into subject categories. Also allows previewing sites.

Yahoo - Basic search engine with many other services.

Metasearch Engines

Big Eye - Metasearch engine that checks the results of 10 search engines.

Debriefing (IxQuick) - Metasearch engine that checks AlltheWeb, Go, Open Directory, Ask Jeeves, Looksmart, Overture, EntireWeb, MSN, Wisenut, FindWhat, Netscape, Yahoo, and Gigablast. Ranks a site according to how many search engines list it in the top ten.

Dogpile - Metasearch engine that checks Google, Yahoo, Ask Jeeves, About, FindWhat, LookSmart, Open Directory, and Overture.

Excite - Metasearch engine with the appearance of a portal that checks Google, Yahoo, Ask Jeeves, About, LookSmart, Open Directory, Overture, Sprinks, FindWhat, Ditto, NewsCrawler and ABCNews.

MetaCrawler - Metasearch engine. Has also gone under the name Go2Net. Includes Metaspy which allows you to see what other people are searching for.

Highway 61 - Metasearch engine that checks Yahoo, Excite, ePilot, Goto, Fast, About, Altavista, Looksmart, Webcrawler, DirectHit, ValleyAlley, and BigWhat.

Mamma - Metasearch engine. Ranks results based on duplicates received from other search engines. Allows you to select which engines are searched.

ProFusion - Metasearch engine that searches Altavista, AlltheWeb, MSN and others.

Search.com - Metasearch engine that searches Google, Ask Jeeves, LookSmart and dozens of others.

Vivisimo - Metasearch engine that clusters results by topic.

WebCrawler - Metasearch engine that checks Google, Yahoo!, Ask Jeeves, About, LookSmart, Overture, and FindWhat.

Specialized Search Engines

ABYZ News Links - Catalog of links to newspapers, news media, and news sources arranged by country.

About.com - Specialized search engine that searches original content and links to other sources selected by subject experts.

Archive-it - A new subscription service offered by the Internet Archive (see Wayback Machine). Any user or institution can create, maintain, or search their own archived web page collections.

CyberCemetery - Creates permanent links to websites and publications of defunct U.S. government agencies and commissions. A partnership between GPO and the University of North Texas Libraries.

Deja News - Specialized search engine that searches Usenet bulletin boards and newsgroups. Acquired by Google.

Electronic Preprints - Catalog of web sites offering electronic preprints of journal articles. Compiled by Goddard Space Flight Center Library.

E-Print Network - "Searchable gateway that provides access to preprint servers from around the world...Links to 18,000 servers in 35 countries housing 650,000 documents."

EuroSeek - Specialized search engine that searches European websites.

FirstGov - Specialized search engine that searches only United States government sites. The official gateway to all U.S. government information.

Google Scholar - Specialized search engine that searches for scholarly literature, including peer-reviewed papers, theses, books, preprints, abstracts and technical reports from all broad areas of research. Use Google Scholar to find articles from a wide variety of academic publishers, professional societies, preprint repositories and universities, as well as scholarly articles available across the web. Google Scholar also automatically analyzes and extracts citations and presents them as separate results, even if the documents they refer to are not online. An Advanced Search option is also available.

Infomine: Scholarly Internet Resources Collections - "INFOMINE is a virtual library of Internet resources relevent to faculty, students and research staff at the university level. It contains useful Internet resources such as databases, electronic journals, electronic books, bulletin boards, mailing lists, online library card catalogs, articles, directories of researchers and many other types of information."

Internet Archive - Also called the Wayback Machine, it is a specialized search engine that searches an archive of old web pages.

Internet Public Library - Catalog of reputable sources selected by the University of Michigan School of Information.

OneKey - Specialized search engine for kids based on Google.

Overture - Specialized search engine that searches only business sites that pay to be included.

Scirus - Specialized search engine that covers only scientific web pages and articles.

Search NASA - Specialized search engine for NASA.gov.

Search NASA via Spacelink - Specialized search engine for NASA offered by Spacelink.

SearchMil - Specialized search engine for military web sites A commercial site not run by DoD.

WWW Virtual Library - Link catalog of reference sites worldwide selected by volunteer subject experts. This is the oldest catalog of the web and was started by Tim Berners-Lee, the creater of HTML.