At present, there is no consistency in the terminology applied to World Wide Web resources or to the tools used to access them.

These modules will use the term "web indexes and directories" for those web access tools which, to a greater or lesser degree, evaluate web sites for reliability before they link to them. Library web site subject pages and faculty web sites can be thought of as special types of web indexes and directories. They are much smaller and much more tightly focused in the subject matter they cover.

• Web indexes are searchable databases of high quality web sites, many of which are academic. They serve web publishing the way print and electronic indexes serve print publishing.
• Web directories generally use an hierarchical structure. Most library subject pages and faculty subject pages are directories more than they are searchable indexes.

Web indexes and directories in general

• organize web-based information
• may be searched by subject term or hierarchically
• often provide abstracts
• in general, assign subject headings or descriptors
• retrieve a few relatively reliable sites rather than everything
• may be subscription or fee-for-service
• may be large and comprehensive
• may be small and tightly focused