No matter what restaurant you go to in America (and many homes as well), if you're eating a sandwich, chances are there will be a pickle on your plate.
It's a tradition that started in the Jewish delis of New York City, but why?
Turns out, pickles were served on the side with sandwiches because the acidity of the vinegar works as a palate cleanser. The sharp tang of a dill, sour, or half-sour pickle lets you taste the rest of the flavors more clearly.
→ Read more: Why Does Your Sandwich Come With a Pickle? from Mental Floss