Everything around you is made of tiny particles called atoms and molecules. They can be packed three different ways:
The hotter something gets, the faster its particles wiggle. At low temperature they barely move, holding tight as a solid. Add heat โ they break loose and slide past each other (liquid). Add more heat โ they fly apart and zoom off (gas).
Take heat away and it goes the other way: gas โ liquid โ solid. Steam โ water โ ice.
Water in your freezer = solid. Water in your bottle = liquid. Steam off your phแป = gas. Same HโO atoms โ only the temperature differs.
This is why a glass of cold drink "sweats" on a hot day โ water gas in the air cools, slows down, becomes liquid, and lands on the cold glass. Condensation.
Heat a gas hot enough and the atoms break apart. That's plasma โ the fourth state. You'd think it's rare, but actually almost everything in space is plasma. The Sun is a giant ball of plasma. Lightning bolts are streaks of plasma.
Cold things have slow particles. Hot things have fast particles. Add or take away energy and the same stuff can become a solid, a liquid, or a gas.
Look at the ice in your drink right now. Every cube is melting because the warmer air is giving its molecules a push. Same water โ being talked into a different form.