Whats the concept of and differences between 'FrameBuffer' and 'RenderBuffer' in OpenGL?

Question

I'm GL newbie, and currently learning.

I'm confusing about concept of FrameBuffer and RenderBuffer. I know that they're required to render, but I want to understand them before use.

I know some bitmap buffer is required to store temporary drawing result. The back buffer. And the other buffer required to be seen on screen during those drawings are in progress. The front buffer. And flip them, and draw again. I know this concept, but it's hard to connect those objects to this concept.

Whats the concept of and differences of them?

Answer 1

This page has some details which I think explain the difference quite nicely. Firstly:

The final rendering destination of the OpenGL pipeline is called [the] framebuffer.

Whereas:

Renderbuffer Object
In addition, renderbuffer object is newly introduced for offscreen rendering. It allows to render a scene directly to a renderbuffer object, instead of rendering to a texture object. Renderbuffer is simply a data storage object containing a single image of a renderable internal format. It is used to store OpenGL logical buffers that do not have corresponding texture format, such as stencil or depth buffer.