In other words, a tokenized attribute type represents a fixed set of keyword types with special meanings. ID Attribute Default ID represents a unique ID name for the attribute that identifies the element within the context of the document. For the most part, ID is used primarily by programs or scripting languages that process the document. The value for ID must be a valid XML name beginning with a letter and containing alphanumeric characters or the underscore character without any whitespace. All ID values used in a document must be different.
IDs uniquely identify individual elements in a document.
The types are used to specify valid names. You might use them when you are associating some other component with the element. You can specify the value of an attribute that must be taken from a specific list of names. There are two kinds of enumerated types Enumeration Attributes can also be defined by a list of acceptable pipe delimited values from which the document author must choose. No External Entity References.