The semantic search is a used process to improve the search by Internet by means of the use of data of the semantic networks to desambiguar the consultations and the text of the Web in order to find the most excellent results in relation to the demand of the user.

Due to the fast evolution of the Web (from the first generation or Web 1,0 happening through Web 2,0 and arriving at 3,0 Web or semantic Web) and the great increase of present contents in Internet like global network, every time it is made more necessary to have efficient methods of information retrieval.

The information retrieval consists of finding the material (normally documents) among great collections of data to satisfy the necessity with a user. The main objective of the recovery system of information must be to obtain the possible most excellent documents in relation to a particular consultation.

Nowadays the use of motors is essential search to realise the consultations in Internet and is possible that a same motor search provides different answers for different versions from a same question. These results can depend on the used key words and not always they are correct.

These are main the motivations for the semantic development of methods search, to take advantage of the properties the semantics (as the study of the meaning of the words) to orient the search and thus to try to obtain optimal results.

The difficulty of this type search falls to which it stops the human beings is easy to establish semantic equivalences between different expressions but this process is not evident for the automated systems. A system search semantic ideal would have to emulate a hypothetical human system search a sufficiently great memory to remember and to relate all the questions and answers previously consulted.

It is certain that different people can give different answers from a same question but no matter how much we reformulate the consultation the answer will be similar since semantically they will be equivalent consultations.

Finally the definitive objective for an artificial system search semantics will be to obtain the same results and in the same order of relevance with respect to different semantically equivalent consultations.

Hildebrand provides a general vision enumerating systems search semantic and identifies other uses of the semantics in the processes search.