Classes have cleaner syntax, use extends/super for inheritance, throw without new, are not hoisted, and are always strict. Constructor functions require manual prototype chain setup and do not enforce new. Classes are syntactic sugar over the same prototype system.

Yes. class Person { greet() {} } puts greet on Person.prototype. extends sets up the prototype chain (Student.prototype.__proto__ = Person.prototype). Under the hood, it is the same prototypal inheritance.

Yes. Calling a class constructor without new throws TypeError: Class constructor Person cannot be invoked without 'new'. This prevents the forgotten-new bug that constructor functions have.