COVAX has four basic aims: dissemination of European Culture Heritage,
facilitating access for European citizens to primary sources of
intellectual, cultural and scientific heritage stored in archives,
libraries and museums; exploitation over the Internet of existing
cultural infrastructures; the use of standards in the field of information
structure and retrieval and interoperability between systems (interoperable
access to distributed resources) based on the complementary capabilities
of each partner.
In addition to being well-formed, an XML document may be valid. This means that it contains a reference to a Document Type Definition (DTD), and that its elements and attributes are declared in that DTD and follow the grammatical rules for them that the DTD specifies.
A DTD is an example of a schema or grammar. Since the initial publication of XML 1.0, there has been substantial work in the area of schema languages for XML. Such schema languages typically constrain the set of elements that may be used in a document, which attributes may be applied to them, the order in which they may appear, and the allowable parent/child relationships.
The design goals of XML include, "It shall be easy to write programs which process XML documents." Despite this, the XML specification contains almost no information about how programmers might go about doing such processing. The XML Infoset specification provides a vocabulary to refer to the constructs within an XML document, but also does not provide any guidance on how to access this information. A variety of APIs for accessing XML have been developed and used, and some have been standardized.
Stream-oriented facilities require less memory and, for certain tasks which are based on a linear traversal of an XML document, are faster and simpler than other alternatives. Tree-traversal and data-binding APIs typically require the use of much more memory, but are often found more convenient for use by programmers; some include declarative retrieval of document components via the use of XPath expressions.
Web site funded by the European Commission.
The site author is solely responsible for its content.
The site does not represent the opinion of the Community and the
Community is not responsible for any use that might be made of data
Reproduction of any part of the site is authorised, except for commercial
purposes, provided the source is acknowledged.
Some of the documents and multimedia sequences on this site might
contain references, or pointers, to information maintained by other
organisations. Please note that we do not control and cannot guarantee
the relevance, timeliness or accuracy of these outside materials.