class 1. The noun class derives fromMedieval French and French classe from Latin classis,probably originally a summons,hence a summoned collection of persons,a group liable to be summoned:perhaps for callassis from calare,to call, hence to summon.
|--Eric Partridge Origins: A Short Etymological Dictionary of Modern English|
Class declarations define new reference types and describe how they are implemented (§8.1).
A nested class is any class whose declaration occurs within the body of another class or interface. A top level class is a class that is not a nested class.