👉 A fluid, in the context of physics and chemistry, is a substance that takes the shape of its container while maintaining a constant volume. Unlike gases, which expand to fill any container regardless of its shape, fluids (both liquids and, in some cases, certain gases) resist changes in volume. Liquids have a definite volume but not a definite shape; they flow and can be molded into the shape of their container. This behavior is due to the cohesive forces between fluid molecules, which are stronger than those in gases, allowing them to maintain a consistent shape while still being able to flow and fill spaces.
