This article talks about Controlled Vocabulary, which is an organized arrangement of words and phrases used to index content and to retrieve content through browsing or searching. It typically includes preferred and variant terms and has a defined scope or describes a specific domain. It is a way to insert an interpretive layer of semantics between the term entered by the user and the underlying database to better represent the original intention of the terms of the user.The most effective communication occurs when all parties involved agree on the meaning of the terms being used. Consequently, finding the right words to communicate the message of your website can be one of the most difficult parts of developing it.