Editing Trie (section)

=== Web search engines ===
A specialized kind of trie called a compressed trie, is used in [[web search engine]]s for storing the [[Web indexing|indexes]] - a collection of all searchable words.<ref name="Xu12">{{cite journal|title=An enhanced dynamic hash TRIE algorithm for lexicon search|first1=Lai|last1=Yang|first2=Lida|last2=Xu|first3=Zhongzhi|last3=Shi|doi=10.1080/17517575.2012.665483|date=23 March 2012|pages=419–432|volume=6|issue=4|journal=Enterprise Information Systems|bibcode=2012EntIS...6..419Y |s2cid=37884057 }}</ref> Each terminal node is associated with a list of [[URL]]s—called occurrence list—to pages that match the keyword. The trie is stored in the main memory, whereas the occurrence is kept in an external storage, frequently in large [[Computer cluster|clusters]], or the in-memory index points to documents stored in an external location.<ref>{{cite journal|first1=Frederik|last1=Transier|first2=Peter|last2=Sanders|volume=29|issue=1|date=December 2010|pages=1–37|doi=10.1145/1877766.1877768|title=Engineering basic algorithms of an in-memory text search engine|url=https://dl.acm.org/doi/10.1145/1877766.1877768|publisher=[[Association for Computing Machinery]]|journal=ACM Transactions on Information Systems|s2cid=932749 }}</ref>