The Invisible Web is made up of thousands of databases and searchable sources that
contain highly targeted and valuable information, and whose content is not seen (indexed)
by traditional search engines. Examples:
News archives
Specialized search engines
Proprietary information such as e-journals and scientific databases
Free resources that require login before use
Interactive tools (such as calculators and dictionaries) and web pages whose URLs are created dynamically
Here are several resources that provide information and access to some of the
"Invisible Web":