The XML Schema specification comes with many different types of strings. What's the difference between them? Here's a quick reference to distinguish them.

Here, the string types are organized hierarchically in accordance with their inheritance structure.

• string Any unicode characters
  
  • normalizedString A string without \r, \n, \t
    
    • token A normalizedString without leading or trailing spaces and without 2 or more consecutive internal spaces
      
      • NMTOKEN A token with any mixture letter, digit, or the characters -\._:
        
      • Name A token that's like an NMTOKEN whose initial character is a letter or one of the characters _:
        
        • NCName A Name without the character :
          
          • ID A NCName; only used for attributes
            
          • IDREF A NCName; only used for attributes
            
          • ENTITY A NCName; only used for attributes
            
• QName An NCName optionally prefixed by an NCName:
  
• Notation An NCName