Monday, August 11, 2008

thesaurus....

first of all, i dont know about thesaurus,i thought it was a book, i didnt thought that it was a dictionary... a very useful dictionary... it helps to improve my vocab..
A thesaurus is similar to a dictionary, but instead of definitions and pronunciations, it contains synonyms and sometimes antonyms.
The first example of this genre, Roget's Thesaurus, was compiled in 1805 by Peter Roget, and published in 1852. Entries in Roget's Thesaurus are listed conceptually rather than alphabetically.
Although including synonyms and antonyms, entries in a thesaurus should not be taken as a list of them. The entries are also designed for drawing distinctions between similar words and assisting in choosing exactly the right word. Unlike a dictionary, a thesaurus entry does not define words.
In information technology, a thesaurus represents a database or list of semantically orthogonal topical search keys. In the field of Artificial Intelligence, a thesaurus may sometimes be referred to as an ontology.
Thesaurus databases, created by international standards, are generally arranged hierarchically by themes and topics. Such a thesaurus places each term in context, allowing a user to distinguish between "bureau" the office and "bureau" the furniture. A thesaurus of this type is often used as the basis of an index for online material. The Art and Architecture Thesaurus, for example, is used to index the national databases of museums, Artifacts Canada, held by the Canadian Heritage Information Network (CHIN)