The rapid growth of Internet resources such as websites, online databases, digital libraries, e-journals, and repositories has made information searching complex. Unlike traditional library collections, internet resources use uncontrolled and inconsistent language, which creates problems in searching and retrieval. To overcome this problem, vocabulary control tools such as subject heading lists and thesauri are used to organize, index, and retrieve internet resources effectively. Vocabulary control in Internet resources refers to the use of standardized and controlled terms to describe, organize, and retrieve online information resources. This document gives overview of vocabulary control of internet resources by subject heading list, thesauri. It also gives overview about display and relationship of terms in thesaurus.