“Steam” in a steamy shower is not the same thing as stream in like a steam engine. The steam you can see is actually tiny droplets of liquid water suspended in the air: it’s the same stuff as clouds or fog.
Air is a mixture of mostly oxygen and nitrogen with some water vapor (and other gasses) mixed in. The water vapor is called humidity. Hot air can hold more water than cold air, so in a steamy shower, hot humid air mixes with colder air in the rest of your bathroom and some of the humidity condenses out into tiny droplets which is “steam” you can see.
Boiling is when liquid water is so hot that it instantly turns to vapor at ambient pressure. But evaporation—slowly turning into vapor—happens at much lower temperatures. You might know evaporation by its more common term: “drying.”
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