IDREF ; XML; ID; Attribute value type; ENTITY ; Attribute
Step-by-step explanation
The attribute "IDREF" or "ENTITY"of the attribute value type can contain an accepted XML name. The IDREF attribute value type is used to reference an element with a specified ID attribute within an XML document.
An attribute is a modifier of an element and can be used to provide additional information about an element. The attribute value type specifies the format of the value assigned to the attribute. In the case of IDREF, the value must be a reference to the ID of another element in the XML document. In the case of ENTITY, the value must be the name of an external entity declared in the document type declaration.
Attributes are part of XML elements. An element can have multiple unique attributes. Attribute gives more information about XML elements. hy define properties of elements. An XML attribute is always a name value pair .