Both are disks of dough folded over a filling; the calzone fritto is generally smaller, and though it is simply called calzone in Puglia (where the dish originated), in other parts of Italy it is often referred to as a panzerotto or a pizza fritta to distinguish it from a baked calzone topped with a little tomato sauce, of the kind pictured here.
A Calzone da Forno can be very nice, and -- as is the case with pizzas -- there are both standard calzoni and innovative calzoni that depend upon the whim of the pizzaiolo.
The standard calzone one finds in Tuscany is filled with prosciutto and mozzarella, while the tomato sauce goes on top. A Calzone Farcito, or Stuffed Calzone, will contain considerably more, for example shredded mozzarella, finely sliced hot dog, sweet Italian sausage, finely sliced salamino piccante (pepperoni in the Anglo-Saxon world), thinly sliced ham, quartered canned artichoke hearts, and pitted olives.
The Calzone pictured here is a Maialona (Porker), with ham, salamino piccante, sausage, hot dogs, and mozzarella, and was prepared by the Bottega del Pizzaiolo in Florence.
You will also find a many other calzone stuffings, ranging from different combinations of meats and cheeses to vegetables (generally with cheese) to fish. In short, calzoni are a delightful universe to explore.