The genesis of Internet is understanding and processing human writeup and expression used in texts online. As www advances technology creeps in faster. The understanding and indexing of contents bu SE algorithms is one such phenomenon.
LSI indexing is done using a mathematical technique called singular value denomination. I do not go deep into this neither. The essence of this write up is that language processing online is coming closer to understand words better – those written by humans.
How LSI works is to complex too understand except those who are specialist. What can be derived is that the algorithms understand correlated terms and phrases. This has introduced a new dimension in writing for the web. Single keyword repetition was much widely followed practice till search engines started negating it or on some instance penalizing the document.
Hence in effort to make search engines understand your write up better use a cloud of words that are closely related. The words should be placed naturally and not forced into the matrix. This are now essential practice in search engine optimization whence taking care of on page factors. Seo re engineering of contents have become a must.
Read my earlier blog to understand semantics in simple words.