Directory sites place each web site in their database in one or more predefined
subject categories following review by a human being.
A web site is included
in a directory site's database only after some human reviewer has judged it to
be useful, informative, or otherwise worthwhile. Typical reasons a site might
be included in the database are because it isn't unique enough, it isn't guaranteed
to remain around for long, or it doesn't meet some other guideline or criteria.
A well laid out directory site defines the set of categories so that there
seems to be only one natural choice at each level for the topic you are searching
for. There is increasing consensus about the set of top-level categories, and
include at least the following twelve:
A good search method for directory sites is called "drilling
down", where you click as fast as possible on the next subcategory at each level
until you get to the one you're interested in. A well designed directory
site will make this drilling down natural, since the structure will make it obvious
which category to choose next at each level. You can take an indirect method
in the search section.
Resources. Some of the major Internet directory sites are
Directory sites were originally called
WWW Virtual Libraries, so you can also find them by
searching for "WWW
Internet Services list provides an interesting historical directory site listing.