What is the difference between a jellyfish and a Portuguese man-of-war?

Jellyfish are free-swimming marine animals belonging to the phylum Cnidaria, characterized by their gelatinous, umbrella-shaped bell and tentacles that can sting. In contrast, the Portuguese man-of-war is not a true jellyfish but a colonial organism made up of specialized polyps and medusoids that work together, giving it a distinctive sail-like structure. While both can deliver painful stings, the Portuguese man-of-war has a more complex anatomy and is often mistaken for a jellyfish due to its similar appearance.