PLAIN SELTZER

Seltzer is simply carbonated water: Flat water that get an addictive effervescence from carbon dioxide. Club soda, typically used in cocktails, has a more mineral-y flavor from chemical compounds, like sodium bicarbonate and potassium sulfate. And tonic water's in an entirely different category. It's sweetened with high-fructose corn syrup and flavored with quinine, which gives it a little bitterness