The spit is a thin iron rod with a pointed end used to cook pieces of meat, the other end has a handle which is used to rotate the pieces of food. Nowadays the skewers are included in barbecues and rotate almost always automatically. To be cooked on the spit, food must be previously greased with oil and marinade multiple times, so that the heat does not dry it off too much or burn it.
On the other hand, the term skewer defines a shorter rod, which can be either of metal or wood. Thanks to its small size, the skewer can be used to cook chunks of meat, fish or vegetables in a pan or on the grill.