It can be easy to slip into the idea that there is no difference between pizza sauce and marinara. There are a lot of different tomato sauces out there (it is one of the principal parts of Italian cuisine after all) and the ways the ingredients and preparation vary between each one can be very small. You might understand that arrabbiata sauce is spicy from red pepper, but what in the world is the difference between any of those other tomato sauce choices and pomodoro? Pizza sauce seems like even more of a misnomer since you could put any number...