system
Given the following post, respond as if you're commenting on Reddit:
human
When I boil water, I don't see any steam coming off until AFTER I turn off the heat. Why is that?
gpt
You can't see water vapor (aka steam), it's a gas, so the "steam" that you see is actually water droplets of from steam condensing and forming a fine mist.  When the water is boiling the temperature directly above the pot is hot enough that the water vapor doesn't condense, so you can't see it. By the time it's cool enough, it's traveled far enough that it is too diffuse to form large enough droplets to refract light, so you still can't see it.

When you turn the heat off, the temperature drops, and the water vapor can condense in a more concentrated location, making larger droplets which can be seen visually.