WHAT ARE SUBJECT DIRECTORIES?
Subject directories, unlike search engines, are created and maintained by human editors, not electronic spiders or robots. The editors review and select sites for inclusion in their directories on the basis of previously determined selection criteria. The resources they list are usually annotated. Directories tend to be smaller than search engine databases, typically indexing only the home page or top level pages of a site. They may include a search engine for searching their own directory (or the web, if a directory search yields unsatisfactory or no results.)
HOW DO SUBJECT DIRECTORIES WORK?
When you initiate a keyword search of a directory's contents, the directory attempts to match your keywords and phrases with those in its written descriptions. Subject directories come in assorted flavors. There are general directories, academic directories, commercial directories, portals and now, vortals. Portals are directories that have been created or taken over by commercial interests and then reconfigured to act as gateways to the web. These portal sites not only link to popular subject categories, they also offer additional services such as email, current news, stock quotes, travel information and maps. Vortals, or vertical portals, (See Lesson 4 for examples) are subject-specific directories, as opposed to the broader, more generalized smorgasbord of subjects and other links commonly found in portals.
NOTE: Today, the line between subject directories and search engines is blurring. Most subject directories have partnered with search engines to query their databases and search the web for additional sources, while search engines are acquiring subject directories or creating their own.
Two subject directories have partnered with and developed their own search engines that are very powerful. You will see them listed in both the search engine and the subject directory categories. Check out the different engine and directory "looks" below:
WHAT ARE THE PROS AND CONS OF SUBJECT DIRECTORIES?
PROS:
Directory editors typically organize directories hierarchically into browsable subject categories and sub-categories. When you're clicking through several subject layers to get to an actual Web page, this kind of organization may appear cumbersome, but it is also the directory's strength. Because of the human oversight maintained in subject directories, they have the capability of delivering a higher quality of content.
They may also provide fewer results out of context than search engines.
CONS:
Unlike search engines, most directories do not compile databases of their own. Instead of storing pages, they point to them. This situation sometimes creates problems because, once accepted for inclusion in a directory, the Web page could change content and the editors might not realize it. The directory might continue to point to a page that has been moved or that no longer exists.
Dead links are a real problem for subject directories, as is a perceived bias toward e-commerce sites.
WHEN DO YOU USE SUBJECT DIRECTORIES?
Like the yellow pages of a telephone book, subject directories are best for browsing and for searches of a more general nature. They are good sources for information on popular topics, organizations, commercial sites and products. When you'd like to see what kind of information is available on the Web in a particular field or area of interest, go to a directory and browse through the subject categories.
EXAMPLES OF SUBJECT DIRECTORIES AND PORTALS :
Subject Directories
Portals (subject directories serving as home pages)
I bet you should be driving towards a masters in internet search by now, why not?Yours Truly,
Ferdinand Che.
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