A dictionary is a book or compilation of alphabetically listed words in a particular language. It is primarily used to search for spelling and meaning of words, etymologies, pronunciation, inflected forms of words, capitalization, synonyms, antonyms, word division, etc. A dictionary also offers many the information about a particular word such as, how to spell the word in plural form, if the word is capitalized or abbreviated, how the word can be broken into syllables, the part of speech of the word, examples in the form of a sentence or expression with the word used correctly. Some dictionaries also come with pictures, contain the meanings of important prefixes and suffixes, the history of the word, different words derived from the main word, addresses of colleges or government offices and population of cities and countries.
Dictionaries commonly come in the form of a book in all sizes, including large and heavy, small or pocket-sized dictionaries. Dictionaries are also available on CD-ROM, which enables finding a word faster, can contain a lot of information, are light-weight, small and compact. Newer forms of dictionaries are available in the form of software running on PDAs or computers. There are also many online dictionaries accessible via the Internet. A data dictionary stores information about the database itself. It may contain information such as, database design information, user permissions, user statistics, database process information, database growth statistics, database performance statistics, tables, views, data elements, and structure, how data elements are encoded and search helps. It is mostly used by database users and application developers as it catalogs the organization, contents, and conventions of one or more databases and establishes consistency throughout a complex database, or across a large collection of databases.
There are many different types of dictionaries for special purposes including learner, bilingual, multilingual, scientifical, historical, biographical, technical and geographical dictionaries. Another variant of a dictionary is the glossary, an alphabetical list of defined terms in a specialized field, such as medicine or science. Learner’s dictionaries are mainly for people learning a particular language, bi-lingual dictionaries is used for translating between languages, technical dictionaries like medical and computer dictionaries are meant for professionals in a particular field. Another type of a commonly used dictionary is the Thesauruses, which list words with similar meanings together mainly useful for writing. The are other dictionaries that focus on one part of language, including dictionaries of idioms or collocations, there are dictionaries that translate between varieties of a single language, such as, British-American dictionaries.
