I am trying to understand at a high level what the differences between `R Markdown` and `R NoteBook`. I know they are interrelated but I would like to figure out how they are related. My understanding is this:

I know R Notebooks are really R Markdown documents but I am confused about the terminologies.

RStudio new file option has both `R Markdown` and `R NoteBook` and selecting either of them opens an `R Markdown` file but with minor differences. **So just trying to figure out why are there two options and what is the difference between the two?** 

[![enter image description here](https://i.stack.imgur.com/oyKmv.png)](https://i.stack.imgur.com/oyKmv.png)

I understand R Notebooks are newly introduced and R Markdown has been there for a while. Part of the confusion could be because I never used `R Markdown` before R Notebook was introduced so my related or more specific question is

**What is R NoteBook doing differently than just using R MarkDown or what new capabilities is R NoteBook bringing?**

All my hits on web search are pointing that R Notebook uses R Markdown but I did not find any help on what is specifically different between the two.