How in the world is something like air considered a fluid? “quite simply a fluid is anything that flows”(knight, 2013). If you think about it you see this in movies all the time, the fog flows down the hill into the town or hot air flowing up off the pavement. Also air exerts pressure on us, approximately 14 pounds of it actually. Also you might be thinking of liquids. While all liquids are fluids not all fluids are liquids. Liquids just happen to be denser than the non liquid fluids; they tend to stay where they are put if they are in a container, unlike a gas. another big difference between liquids and gasses is that a gas is compressible, with all that room between the molecules you can squeeze that into a container such as a  balloon. Which is why the balloon inflates, that air inside is compressed until it pushes the rubber into the round shape we all know and love.

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Wait! If air is a fluid can a sharknado really happen? No, while air is a  fluid, it is not liquid saltwater which the sharks require to survive. We shouldn't see to many deaths by flying sharks inland, the odd hurricane not withstanding