The Free On-line Dictionary of Philosophy (FOLDOP) is a searchable dictionary of philosohical terms.
It aims to provide a one-stop source of information about all philosophical terms and includes many useful cross-references and pointers to related resources elsewhere on the Internet, as well as bibliographical references to paper publications. It also contains many definitions in related areas such as mathematics and computer science.
The dictionary is based on Denis Howe's FOLDOC. This started in 1985 and has grown, with the help of nearly 1200 contributors, to contain over 12000 definitions totalling 4.7 megabytes of text. Both FOLDOC and FOLDOP are freely available on the Internet via the World-Wide Web.
All searches are logged and a list of frequently requested missing terms is also available on-line. Users are encouraged to contribute definitions of missing terms. These contributions are usually edited extensively before inclusion. New terms are added almost every day.
The dictionary is stored as a single source file in a simple, easy-to-edit, human-readable form of mark-up which is converted to HTML on the fly by a Perl CGI program. The program uses a custom matching algorithm to provide fast, flexible, indexed searches of headings as well as full-text searches. Other Perl programs build the index, the lists of missing terms, and the contents pages.