Introduction
Some web sites exist that are generated specifically towards one area, for example medical journal, financial information and statistical data. These web pages may sometimes be overlooked by search engines or you may need to pay a subscription fee in order to access the information.
Other web sites may only be accessible through your work or an organisation. For example, most college libraries assign each student a user name and password. This allows them to have privileged access to selected web pages that ordinary users would not have.
The Invisible Web
There are millions of web pages and links across the Internet. What we access through search engines only covers a fraction of what is actually available to us.
Search engines are unable to index all these pages. Non-textual files such as multimedia files, graphic files, and documents in non-standard formats such as PDF are sometimes overlooked by the spiders of search engines (although Google now includes an option to search for PDF files that it has re-written to HTML). This area that is not data based is known as the Invisible or Deep Web. It is thought that the size of the Invisible Web could be up to 500 times larger than the surface Web according to Bright Planet Corporation.
How to access the Invisible Web?
They are many specialised search engines that claim to search the web pages of those that are ‘lost’ to the Deep Web. These include http://www.invisibleweb.com, www.profusion.com, www.incywincy.com
Referencing the Web
There are a number of formats to referencing web pages that you have used for research, or may have quoted. However, the principle (apart from some differences) remains the same as if you were sourcing a book or journal. You should include the author of the site, the date it was posted on the webpage or last revised, the date you accessed the information, the URL and the title of the work (if there is one).
You may not have all these references but try to include as many as you can. This way, people who are interested in what you have written know where to follow up on your research, if they want to get more information.
