A Namespace is a set of unique names. Namespace is a mechanisms by which element and attribute name can be assigned to a group. The Namespace is identified by URI(Uniform Resource Identifiers).
A Namespace is declared using reserved attributes. Such an attribute name must either be xmlns or begin with xmlns: shown as below −
<element xmlns:name = "URL">
The Namespace starts with the keyword xmlns.
The word name is the Namespace prefix.
The URL is the Namespace identifier.
Namespace affects only a limited area in the document. An element containing the declaration and all of its descendants are in the scope of the Namespace. Following is a simple example of XML Namespace −
<?xml version = "1.0" encoding = "UTF-8"?> <cont:contact xmlns:cont = "www.tutorialspoint.com/profile"> <cont:name>Tanmay Patil</cont:name> <cont:company>TutorialsPoint</cont:company> <cont:phone>(011) 123-4567</cont:phone> </cont:contact>
Here, the Namespace prefix is cont, and the Namespace identifier (URI) as www.tutorialspoint.com/profile. This means, the element names and attribute names with the cont prefix (including the contact element), all belong to the www.tutorialspoint.com/profile namespace.