The type can be one of ID, IDREF, IDREFS, ENTITY, ENTITIES, NMTOKEN, NMTOKENS,

NMTOKENS is a list of NMTOKEN separated by spaces.

Legitimate values are ID, IDREF, IDREFS, ENTITY, ENTITIES, NMTOKEN, NMTOKENS, NOTATION, CDATA, and ENUMERATION.

The USAddress definition contains only declarations involving the simple types: string, decimal and NMTOKEN.

This term is an XML NMTOKEN that specifies the name of the event that is raised on the Event-base element.

For example, the NMTOKEN value US is indivisible in the sense that no part of US, such as the character "S", has any meaning by itself.

In addition, Id-values and Event-symbols are XML NMTOKEN values and as such are allowed to contain the full stop '.' and hyphen-minus '-' characters.

For those who are aware of how DTDs and other schemas work: The xml:lang attribute takes NMTOKEN values in the XML schema, so they cannot be empty.

For example, NMTOKENS is a list type, and an element of this type would be a white-space delimited list of NMTOKEN's, such as "US UK FR".

Further, since the set of legal values for attributes of type ID is much smaller than for those of type CDATA, the type of the name attribute has been changed to NMTOKEN.

Notes: (1) To retain compatibility between XML Schema and XML 1.0 DTDs, the simple types ID, IDREF, IDREFS, ENTITY, ENTITIES, NOTATION, NMTOKEN, NMTOKENS should only be used in attributes.