What are the differences between a Frame Buffer Object and a Pixel Buffer Object in OpenGL?

Question

What is the difference between FBO and PBO? Which one should I use for off-screen rendering?

Answer 1

I would read VBOs, PBOs and FBOs:

Apple has posted two very nice bits of sample code demonstrating PBOs and FBOs. Even though these are Mac-specific, as sample code they're good on any platoform because PBOs and FBOs are OpenGL extensions, not windowing system extensions.

So what are all these objects? Here's the situation: