what components can crude oil be separated into?

Answer 1

Crude oil is separated through multiple levels of distillation.

The lightest components are made into natural gas--propane, butane, etc.
The next components become gasoline--pentanes, hexanes, heptanes, etc.
The next higher components often get used as jet fuel, then ship fuel, then waxes, then asphalt.

Many of the small components, especially the 2-6 carbon range, often get transformed into other chemical of industrial importance and converted into polymers, but unlike what the first answerer said, you don't get polymers directly out of the oil.

You can get WAY more details here:
List of major products: http://en.wikipedia.org/wiki/Petrochemical
Description of an oil refinery: http://en.wikipedia.org/wiki/Oil_refinery

Answer 2

carbon polymers (plastics)
Methane-like(longer chains) Fuels