A balloon is a flexible, lightweight bag—often made of latex or rubber—that’s inflated with air or lighter-than-air gases like helium. When filled, it expands into a smooth, rounded shape, available in various sizes, with the standard party‑balloon measuring around 11 inches (about 28 cm) when fully inflated. Balloons come in an array of bright colors and designs, serving as festive decorations, children’s toys, or the base for balloon art and sculptures. Latex versions are biodegradable but let helium seep through over time, typically remaining buoyant for 8–12 hours, while foil balloons hold gas longer. Beyond parties, balloons also have scientific, meteorological, and industrial uses—ranging from weather observation to aerial advertising—highlighting their wide-ranging versatility.