A fractionating column for crude oil (used in fractional distillation)

A fractionating column is a tall column that has chambers/points at different temperatures.

For distilling crude oil you would have the following:

$A fractionating column is a tall column where crude oil is heated where the liquid is siphoned off at different points to provide oil, fuel, and gasses to be used for different things$

Hydrocarbon chains have different condensing temperatures so when a 20 carbon atom hydrocarbon molecule (C₂₀) passes through a chamber that is at its condensing temperature, it will turn from vapour into liquid (i.e. it will condense).