Apache Lucene is a free and open-source search engine software library, originally written in Java by Doug Cutting.

[2][3][4] Lucene has been ported to other programming languages including Object Pascal, Perl, C#, C++, Python, Ruby and PHP.

In March 2010, the Apache Solr search server joined as a Lucene sub-project, merging the developer communities.

[10][11] Lucene includes a feature to perform a fuzzy search based on edit distance.

Lucene itself is just an indexing and search library and does not contain crawling and HTML parsing functionality.