Organization and Scope of Content
ODP uses a hierarchical ontology scheme for organizing site listings. Listings on a similar topic are grouped into categories, which can then include smaller categories.
Gnuhoo borrowed its initial ontology from Usenet. For example, the topic covered by the comp.ai.alife newsgroup was represented by the category Computers/AI/Artificial_Life. The original divisions were for Adult, Arts, Business, Computers, Games, Health, Home, News, Recreation, Reference, Regional, Science, Shopping, Society, and Sports. While these fifteen top-level categories have remained intact, the ontology of second- and lower-level categories has undergone a gradual evolution; significant changes are initiated by discussion among editors, and then implemented when consensus has been reached.
In July 1998, the directory became multilingual with the addition of the World top-level category. The remainder of the directory for English language sites only. By July 2003, sixty-seven languages were represented. While the English component of the directory held almost 75% of the sites, the growth rate of the non-English components of the directory was greater than the English component through 2002 and 2003. Ontology in non-English categories generally mirrors that of the English directory, although exceptions which reflect language differences are quite common.
Several of the top-level categories have unique characteristics. The Adult category is not present on the directory homepage, but it is fully available in the RDF dump that ODP provides. While the bulk of the directory is categorized primarily by topic, the Regional category is categorized primarily by region. This has led many to view ODP as two parallel directories: Regional and Topical.
On November 14, 2000, a special directory within the Open Directory
was created for people under 18 years of age. Key factors
distinguishing this "Kids and Teens" [1] area from the main directory are:
- Stricter guidelines which limit the listing of sites to those which are targeted or appropriate for people under 18 years of age.[1]
- Category names as well as site descriptions use vocabulary which is age appropriate.
- Age tags on each listing distinguish content appropriate for kids (age 12 and under), teens (13 to 15 years old) and mature teens (16 to 18 years old).
- Kids and Teens content is available as a separate RDF dump.
- Editing permissions are such that the community is parallel to that of the Open Directory.
By