Applications of carbon dioxide by humans
Humans use carbon dioxide in many different ways. The most familiar example is its use in soft drinks and beer, to make them fizzy. Carbon dioxide released by baking powder or yeast makes cake batter rise.
Some fire extinguishers use carbon dioxide because it is denser than air. Carbon dioxide can blanket a fire, because of its heaviness. It prevents oxygen from getting to the fire and as a result, the burning material is deprived of the oxygen it needs to continue burning.
Carbon dioxide is also used in a technology called supercritical fluid extraction that is used to decaffeinate coffee. The solid form of carbon dioxide, commonly known as Dry Ice, is used in theatres to create stage fogs and make things like "magic potions" bubble.