There are many things that you can order at in n out but there is also a secret menu that is not on the ordinary menu but you have to ask the workers
Animal Style:
This can be applied to both burgers and fries. For burgers, it means mustard-cooked patties, pickles, extra spread (their special sauce), and grilled onions. For fries, it means cheese, spread, and grilled onions.
Protein Style:
This swaps the bun for lettuce wraps, making it a lower-carb option.
Flying Dutchman:
This is a simple combination of two beef patties and two slices of cheese, with no bun or vegetables.
3x3 (Triple-Triple) / 4x4 (Quad-Quad):
These refer to burgers with three or four patties and cheese slices, respectively.
Drinks:
In-N-Out offers custom shakes like the Neapolitan (chocolate, vanilla, and strawberry) and the Black and White (chocolate and vanilla). You can also order a Root Beer Float (vanilla shake and root beer) or an Arnold Palmer (lemonade and iced tea).
Other customizations:
You can request extra toppings like chopped chilies, extra spread, or well-done or light-cooked fries.