Can I name additional data stream types used in RxJava besides Observable?

In RxJava, besides the basic Observable type, there are other data stream types that offer different capabilities and semantics:

• Single — emits exactly one item or an error. Used when one result is expected, such as a network response.
• Maybe — can emit one item, nothing, or an error. Combines the behavior of Single and Completable.
• Completable — does not emit items but only signals successful completion or an error. Useful for operations without a result, such as writing to a database.
• Flowable — similar to Observable but supports backpressure, which is important when working with large data streams.

Example of using Single:

Single<String> single = Single.just("Hello");
single.subscribe(
    item -> System.out.println("Received: " + item),
    error -> System.err.println("Error: " + error)
);