Each webring is maintained by a volunteer at an uninvolved site using standard software. Specialty Tools Not all search engines are global, and the regional or topic-specific search tools are valuable in searching a more tightly focussed collection. Topic-Specific Search Engines . A particularly emergent approach is to search for a search engine which only indexes webpages on particular topics. Finding such a search engine is not simple as frankly there are not that many that exist yet.
Most lists mix in searchable collections and online databases.
Ideally you will find a search engine like ChemGuide covering over a million chemistry related pages. Read the Altavista Fancy Features for Typical Searches . A unique resource. Field searches are optional, so just enter search terms in title box for a title search. Altavista also allows for a field search by language.