Imagine you're making pasta. You fill a pot with water and place it on the stove. As the heat from the stove transfers to the water, the water molecules start to move faster and faster. Eventually, they have so much energy that they break free from the liquid state and turn into a gas – water vapor. This is boiling.

You can see the evidence of boiling in several ways:

* Bubbles: The bubbles that form in the water are pockets of steam (water vapor) that are escaping from the liquid.

* Steam: The steam rising from the pot is the visible form of the water vapor.

* Temperature: The temperature of the water stays at 100°C (212°F) during the boiling process, even as you continue to heat it. This is because all the energy being added is going towards turning the liquid water into steam.

So, when you see those bubbles and hear that gurgling sound, you know your water is boiling!