Simplify the following text for a Grade 14 native English-speaking person.
Original: The Mathematics Subject Classification ( MSC ) is an alphanumerical classification scheme collaboratively produced by staff of based on the coverage of the two major mathematical reviewing databases Mathematical Reviews and Zentralblatt MATH .
Simplified: The Mathematics Subject Classification ( MSC ) system is an alphanumeric ordering system for categorizing or arranging mathematical topics , similar to how a library arranges or orders their books on the shelves . The system was invented by the American Mathematical Society based on two major mathematical publishers : Mathematical Reviews and Zentralblatt MATH .