General 3DSM6 Qs

I need to learn the simple stuff while still can. It’s going to take me years to learn this. Sorry if these questions sound retarded.

What is:[list]
[]Organic Modelling
[
]Irradiance
[]Photons
[
]Caustics
[]Radiosity
[
]RayTrace
[*]Normals
[/list]
God I feel like a dumba** :(. If you can explain these and the uses of them, I’d be grateful. Thanks a lot :).