system
Given the following post, respond as if you're commenting on Reddit:
human
In regards to classification (E.G.: Solid, Gas, Liquid, etc) What is fire?

This is a question my family asked in a recent discussion. It obviously isn't a solid or liquid, but it isn't exactly a gas either, right?
gpt
The fire you see is just the effect of incandescence. When atoms are heated up to that degree they emit light, hence the visible flame. The variation in colours depends on what you're burning.

The conglomeration of atoms that comprise the flames you see would be classified as a gas.