What are the ways to create observables that you know?

• create(): Allows creating an Observable from scratch, managing data emission manually.
• just(): Creates an Observable that emits a single item.
• fromArray(): Creates an Observable from an array of items.
• fromIterable(): Creates an Observable from any collection implementing Iterable.
• interval(): Creates an Observable that emits a sequence of integers at specified time intervals.
• timer(): Creates an Observable that emits zero after a specified delay, then completes.
• range(): Creates an Observable that emits a sequence of integers within a specified range.
• empty(): Creates an Observable that emits no items and completes immediately.
• error(): Creates an Observable that immediately emits an error.
• never(): Creates an Observable that emits no items and never completes.
• defer(): Creates an Observable that is generated lazily after each subscription.

// Example with just()
Observable<String> singleItemObservable = Observable.just("Hello");

// Example with fromArray()
String[] items = {"A", "B", "C"};
Observable<String> arrayObservable = Observable.fromArray(items);

// Example with create()
Observable<Integer> customObservable = Observable.create(emitter -> {
    try {
        for (int i = 0; i < 5; i++) {
            emitter.onNext(i);
        }
        emitter.onComplete();
    } catch (Exception e) {
        emitter.onError(e);
    }
});