Kielbasa is a type of sausage from Poland. Typically made with ground pork, beef, or a blend of the two, it is often smoked and has a distinct flavor. In contrast, sausage is a broad term that describes any seasoned ground meat stuffed into a casing. Sausages are made from a variety of meat, including pork, beef, chicken, and turkey. It's worth noting that while kielbasa is a type of sausage, not all sausages are considered kielbasa.