A panini is a grilled sandwich that is traditionally made on Italian bread. The bread is filled with meats, cheese and vegetables. The outside of the bread is then brushed with olive oil and placed on a special grill with grooved plates. Both the top and bottom grill plates heat up to toast the bread and add distinctive grill marks. Panini grills can also be used to cook food items other than sandwiches. Small steaks, fish fillets, chicken breasts and vegetables are other foods that they are used for. Also, it is not a requirement that you have a grill with grooved plates. There is the option of having smooth top and bottom plates, or one smooth and one grooved. If you are going to be creating a large quantity of Panini sandwiches, you may want to consider getting a grill with a split top. Split top units essentially have two grills side-by-side. Though these models are large than full-top paninis, so you will want to check and make sure there is enough countertop space available.