Key features - Support for http, https, ftp, nntp and news URL schemes. - htdb virtual URL scheme support for indexing SQL databases. - text/html, text/xml, text/plain, audio/mpeg (MP3) and image/gif MIME types built-in support. - External parsers support for other document types. - Ability to index multilangual sites using content negotiation. - Searching all of the word forms using ispell affixes and dictionaries. - Stopwords, synonyms and acronyms lists. - Boolean query language support. - Results sorting by relevance, popularity rank, last modified time and by importance (a multiplication of relevance and popularity rank). - Various character sets support. - Phrases segmenting for Chinese, Japanese, Korean and Thai languages. - Accent insensitive search. - mod_dpsearch - a search module for Apache web server (both 1.x and 2.x branches). - Internationalized Domain Names support. - The Summary Extraction Algorithm.