Associative Links: it is a link that is completely independent of the exact structure of the information. For illustration we have links depends on the meaning of various information components. The most general example that most people would be familiar along with is cross-referencing inside books for illustration: for more information on X consider to Y. this is these relations or rather the links that are a representation of the relations that provide the essence of hypermedia and in many respects can be considered to be the defining feature of hypermedia.