The Invisible Web refers to the part of the WWW that’s not indexed by the search engines. Most of us think that that search powerhouses like Google and Bing are like the Great Oracle”¦they see everything. Unfortunately, they can’t because they aren’t divine at all; they are just web spiders who index pages by following one hyperlink after the other. But there are some places where a spider cannot enter. Take library databases which need a password for access. Or even pages that belong to private networks of organizations.
By Danny Sullivan From The Search Engine Report Aug. 2, 2000 I've written before about the "invisible web," information that search engines cannot or refuse to index because it is locked up within databases. Now a new survey has made an attempt to measure how much information exists outside of the search engines' reach. The company behind the survey is also offering up a solution for those who want tap into this "hidden" material. The study, conducted by search company BrightPlanet, estimates that the inaccessible part of the web is about 500 times larger than what search engines already provide access to. Invisible Web Gets Deeper
Search engines are, in a sense, the heartbeat of the internet; “googling” has become a part of everyday speech and is even recognized by Merriam-Webster as a grammatically correct verb. It’s a common misconception, however, that googling a search term will reveal every site out there that addresses your search. In fact, typical search engines like Google, Yahoo, or Bing actually access only a tiny fraction – estimated at 0.03% – of the internet.
While burying yourself in the stacks at the library is one way to get some serious research done, with today’s technology you can do quite a bit of useful searching before you ever set foot inside a library. Undergraduates and grad students alike will appreciate the usefulness of these search engines that allow them to find books, journal articles and even primary source material for whatever kind of research they’re working on and that return only serious, academic results so time isn’t wasted on unprofessional resources. Note: Visit our updated list for the latest in academic search engines. General Start off your research with one of these more general academic search engines.
The Internet has proven itself as a valuable resource for all types of readers, from collectors of rare books to tech-minded readers who shop, network and download books online. But if you’re having trouble finding exactly what you need, whether it’s a book review, a book by a certain author, or a digitized anthology for your class at an online college for creative writing, you’ll want to use sophisticated tools that direct you to high-quality resources. Here are 50 cool search engines for serious readers and students.
College researchers often need more than Google and Wikipedia to get the job done. To find what you're looking for, it may be necessary to tap into the invisible web, the sites that don't get indexed by broad search engines. The following resources were designed to help you do just that, offering specialized search engines, directories, and more places to find the complex and obscure. Search Engines Whether you're looking for specific science research or business data, these search engines will point you in the right direction. Turbo10: On Turbo10, you'll be able to search more than 800 deep web search engines at a time.
What is the Invisible Web? How can you find it online? What makes the Invisible Web search engines and Invisible Web databases so special? Find out the answers to these questions and learn more about this section of the Web that's so much larger than what you can uncover with an ordinary Web search.
Whether you're looking for the average rainfall in the Amazon rainforest, researching Roman history, or just having fun learning to find information, you'll get some great help using my list of the best research and reference sites on the Web. About.com: I've found many answers to some pretty obscure questions right here at About. Reference.com.Extremely simple to use, very basically laid out.
Mike Bergman, founder of BrightPlanet and credited with coining the phrase, said that searching on the Internet today can be compared to dragging a net across the surface of the ocean: a great deal may be caught in the net, but there is a wealth of information that is deep and therefore missed. Most of the Web's information is buried far down on dynamically generated sites, and standard search engines do not find it. Traditional search engines cannot "see" or retrieve content in the deep Web—those pages do not exist until they are created dynamically as the result of a specific search. As of 2001, the deep Web was several orders of magnitude larger than the surface Web. Size
Des moteurs comme Google, MSN/Live Search, Yahoo! Search ou des répertoires tels que Yahoo! Directory ne vous donnent accès qu'à une petite partie (inférieure à 10%) du web, le Web Visible. La technologie de ces moteurs conventionnels ne permet pas d'accéder à une zone immense du web, le Web Invisible, espace beaucoup plus important que le web visible. Lors d'une navigation en Antarctique pour prélever des échantillons de glace sur des icebergs, si vous vous limitez à leur partie émergée, vous vous privez de la surface immergée, en moyenne 50 fois plus importante.
Deep Web, the hidden Internet | ePagini News, Articles,Opinions and Reviews
What is the "Invisible Web", a.k.a. the "Deep Web"? The "visible web" is what you can find using general web search engines. It's also what you see in almost all subject directories. The "invisible web" is what you cannot find using these types of tools. The first version of this web page was written in 2000, when this topic was new and baffling to many web searchers. Since then, search engines' crawlers and indexing programs have overcome many of the technical barriers that made it impossible for them to find "invisible" web pages.
Introduction [dernière mise à jour : juillet 2012] Internet a changé la donne pour la diffusion des bases de données bibliographiques et factuelles. Les universités, laboratoires de recherche et même les offices de brevets proposent leurs bases de données en accès gratuit. Sachez que ces ressources sont mal signalées par les moteurs de recherche car l'information est diffusée sous forme de pages dynamiques pas toujours indexées par les robots. On en parle sous le nom de web invisible. Bien que gratuites, les bases de données sont protégées (voir Database protection activities).
The Invisible Web
How Deep Is The web