How the CCS works: metadata

Simple search engines

Simple search engines make no attempt to ascertain the context in which a search term is being used. All they do is mechanically retrieve all pages containing that term. If a person, looking for information to help them with their housing problem, entered the search term, 'housing', they'd be presented with a bewildering 97,000,000 pages on subjects ranging from 'underwater video camera housing' to the 'Bank of Housing and Finance in Korea'. If they searched for information on 'eviction', they'd be as likely to get information on the latest eviction from the Big Brother house as helpful information on what to do about a notice to quit.

Metadata schemes

Metadata schemes attempt to solve this problem. Metadata can be thought of as a label containing different fields describing key characteristics of a webpage. While invisible to site users, search engines can be set to scan particular fields of metadata for the search term entered instead of scanning the entire contents of the page. This should vastly reduce the amount of irrelevant information returned by a search.

Dublin Core

Different metadata schemes will use different fields, but they will typically be selected from the Dublin Core. Dublin Core is an international standard for describing information. The name comes from a series of workshops held in Dublin, Ohio in 1995. Simple Dublin Core provides a useful set of elements with which to describe the contents of a webpage, or indeed any other information, including: title, subject, description, author, publisher and date (a full list of all the Dublin Core elements is available by clicking on the link at the right of the page under the heading, 'Links to other websites').

LAMS

The Legal and Advice Sectors Metadata Scheme (LAMS) uses three elements from the Dublin Core: title, description, and subject. Websites are required to produce metadata containing at least these three fields to obtain the CLS Quality Mark. The metadata also complies with e-Government Metadata Standard in the UK (see link).

The subject field should be completed using the CCS preferred term which best describes the subject dealt with by that particular webpage (see CCS Thesaurus version 1.41 (607 KB)). This increases the chance of the information being found on websites such as CLS Direct and Advicenow.

The search engines on these sites scan the subject field for the search term entered by users. They retrieve all pages catalogued by the relevant CCS term, whether the user chooses the CCS preferred term itself as their search term or any of the synonyms for it contained in the CCS thesaurus.

February 2007