Chowder differs from soup primarily in its thicker, creamier consistency and heartier ingredients. Typically, chowders are rich and often milk- or cream-based, giving them a distinctive, velvety texture. They usually include chunky ingredients like potatoes, seafood, or corn, and are often thickened with a roux or crushed crackers. In contrast, soups can vary widely in consistency and ingredients, ranging from broths to purees, and don't necessarily have the same creamy or thickened characteristics as chowder.