In Oil Refining, what are the differences between Polymerization, Catalytic Reforming, and Alkylation?

These all seem to be the same thing. Taking the hydrocarbons, and combining them to make a longer hydrocarbon chain. But what is done differently? Who developed each would be awesome, but I'm not going to expect anyone to know that....In Oil Refining, what are the differences between Polymerization, Catalytic Reforming, and Alkylation?
Catalytic reforming doesn't make the hydrocarbons longer, it changes the structure to increase the octane rating and quite often breaks long chains down. Polymerization joins hydrocarbons and alkylation takes an alkyl (ie butyl, methyl) from one hydrocarbon chain and adds it to a different one. Hope it helps :)