A panini is a form of Italian sandwich where you use a whole bread instead of slices to make the sandwich. The Panini is a form of brown bread that looks similar to a hot dog bread, except that it is more crispy. Depending on how you like the panini, it can have just cheese inside or you can pretty much put in anything else that you like.
Making a panini sandwich is not easy with a sandwich maker because it is much larger and you do not get sandwich toasters in this size. The alternative is to use a toasting oven or a sandwich grill. This is sometimes also called a panini maker.
The sandwich grill is nothing but a simple grill with a heating element on both sides so that the bread browns evenly on both sides. It is just a smaller electric grill on which you can toast your sandwiches and paninis. The grill is covered with non stick material so that your bread does not stick to it.
A panini maker is actually a very good option to have at home simply because it costs a little lesser than the toaster oven but works just as well. Most of them cost around the $40 mark which is the same as most four slice toasters. The difference is that the same grill can be used to make pretty much anything you want as long as it is not too big. A four slice toaster may be smaller, but it will only toast bread.
As a multi-purpose kitchen appliance a sandwich grill is one of the best things to have. It is not so large that you cannot use it as a counter top appliance while at the same time it is not so small that you can make just two sandwiches at the same time. In fact they cost just the same as a dual sandwich maker, but you can make three at a pinch. They also cost the same. The only negative if at all is that you will not get sealed sandwiches, but then for many of us the fun in eating a sandwich is when the cheese runs down the sides. A sealed sandwich also takes much longer to cool and there would be many who have burned the roof of their mouths at the first bite into one without realizing that the inside does not cool as fast as the outside.