These are pretty explanatory, but for those who are at the fourth row, a progressive party needs a bunch of willing victims who could cook up something for every meal course, and the party bunch visits each meal-course-house as the meal progresses. So you'd have aperitifs at Casey's, main course dishes at Hannah's,
cocktail salad dishes at Gary's, and dessert at Russ'. A potluck, on the other hand, requires all daters to bring foods of their own at the potluck party. Just make sure everyone knows what everyone's going to bring, to avoid messing the party up.
