What is the difference between the different types of sausages, salamies, and pepperonies?

Like chorizo, pepperoni, Genoa pepperoni, salami, pastrami, bologna, Andouille sausage, Bavarian sausage, German sausage, bratwurst, hot dog, New York hot dog, Chicago hot dog, Polish sausage, Italian sausage and Vienna sausage
Answers

Trivial One

The kinds of meat used, the ratio of meat to fat, the kinds of seasonings used, whether smoked or fresh , whether it's cured or not, if cured, how, aged or not, how long, the coarseness of the grind of the meat.

CB

Ingredients, and curing process (or lack thereof)

thebax2006

Ingredients and taste.

StarShine

The differences are in the spices added, the meat they're made with, the method they're cured with and the resulting flavours.

Clive

The ingredients and how they are made.

Bertsta

The type of meat(s) used, the part of the animal the meat(s) came from, the amount and type of fillers (fat content. spices, herbs, bulking agents), how they are manufactured, how long and how they are aged/cured.