Cold brew is a coffee brewing method where coffee grounds are steeped in cold water for an extended period, typically 12 to 24 hours, resulting in a smooth and less acidic concentrate that is later diluted with water or milk before serving. On the other hand, iced coffee is traditionally brewed hot and then cooled down by pouring it over ice, and it can be served with milk or ice cream, offering a different flavor profile compared to cold brew.