Comparison of Angular `Subject` and `BehaviorSubject`

subject.ts

var behaviorSubject = new Rx.BehaviorSubject(0); 
var subject = new Rx.Subject();

subject.subscribe(v => {
  console.log('SubjectObserver: ' + v)
});

behaviorSubject.subscribe(v => {
  console.log('BehaviorSubjectObserver: ' + v)
});

behaviorSubject.next(1);
behaviorSubject.next(2);

subject.next(1);
subject.next(2);