Quick: what's in a calzone? And how is that different from what is in a stromboli?
A calzone is a single serving. Meats, vegetables, cheese, especially mozzarella. Can be deep-fried or brushed with oil and baked. Whether it uses sauce or not isn't made clear by The Food Lover's Companion. Specialty of Naples.
Stromboli is a Philly thing, a sandwich-like creature of cheese and usually pepperoni. Food Lover's doesn't say whether it's baked.
Italian-Americans say a calzone has ricotta cheese and a stromboli doesn't. A calzone is served with sauce on the side. Philadelphians say a stromboli is an inside-out pizza; add ricotta cheese to make it a calzone. Some say a calzone is folded and a stromboli is rolled.
Maybe calzone and stromboli were once quite distinct, but as Italian ways became American ways, the Philly stromboli became indistinguishable from the Italian calzone. Like buttermilk pie/chess pie/ transparent pie: There was once a difference but it has eroded away.
If there is a definitive difference -- or an especially dramatic historic schism that cleaved the Calzonites from the Strombolists -- bring it to Bites.