An XML schema defines the structure, content and semantics
of XML documents.
An XML schema defines
the elements that
are allowed
for each element, the attributes that are allowed including
ranges of allowed values and whether or not the attribute
is compulsory
the hierarchical structure of elements, including the order and
number of child elements
for each element, whether or not it
may contain text
data types
default values for elements and attributes
The purpose
of an XML schema is essential the same as
DTD (Document type definitions). XML schemas are more flexible and
extensible that DTD, making them more suitable for many applications.
Other topics in our resources on XML related to XML Schema include: