Editing Library classification (section)

==Comparing library classification systems ==
As a result of differences in notation, history, use of enumeration, hierarchy, and facets, classification systems can differ in the following ways:
* Type of Notation: Notation can be pure (consisting of only numerals, for example) or mixed (consisting of letters and numerals, or letters, numerals, and other symbols). 
* Expressiveness: This is the degree to which the notation can express relationship between concepts or structure.
* Whether they support mnemonics: For example, the number 44 in DDC notation often means it concerns some aspect of France. For example, in the Dewey classification 598.0944 concerns "Birds in France", the 09 signifies geographic division, and 44 represents France.
* Hospitality: The degree to which the system is able to accommodate new subjects.
* Brevity: The length of the notation to express the same concept.
* Speed of updates and degree of support: The better classification systems are frequently being reviewed.
* Consistency 
* Simplicity
* Usability