The fizzy bubbles in soda are created when carbon dioxide gas (CO₂) is dissolved into the beverage under high pressure. When the bottle or can is opened, the gas escapes, forming bubbles and giving soda its characteristic fizz. Carbon dioxide not only provides those appealing bubbles but also contributes to the sharp, tangy taste sensation that makes sodas refreshing. Early carbonated beverages were actually sold as medicinal remedies, believed to cure ailments due to their bubbly, invigorating properties.