LSI stand for: Latent semantic indexing Latent semantic indexing helps search engines to find out what a web page is all about. It basically means to you that you shouldn't focus on a single keyword when optimizing your web pages and when getting links.
Lsi stand for latent semantic indexing.Its information retrieval model build upon the prior research in information retrieval and using the singular value decomposition to reduce the dimensions of the term document space.Lsi can not be used to improve the search engine listing is nothing more than a concept.