👉 Fluid, in its most comprehensive sense, encompasses all substances that have the properties of both liquids and gases, but more specifically refers to the vast array of liquids and gases that make up our world. This includes water, which exists in liquid form on Earth's surface and as vapor in the atmosphere, but also in various liquid states beneath our feet, such as oil, gasoline, and blood. Beyond liquids, fluids extend to gases like steam, carbon dioxide in the atmosphere, and even the plasma found in stars and lightning. The term fluid is also applied to non-liquid states of matter, such as molten rock or supercritical fluids, which exhibit properties intermediate between liquids and gases. The fluidity of substances is crucial for life, enabling processes like circulation in living organisms, weather patterns, and chemical reactions. This extensive range of fluid states highlights the dynamic nature of matter and its essential role in sustaining life and shaping our environment.
