Diet Coke
Diet Coke (called Coca-Cola Light in some countries) is a sugar-free and no-calorie soft drink produced and distributed by The Coca-Cola Company. It contains artificial sweeteners instead of sugar. Unveiled on July 8, 1982 and introduced in the United States on August 9, it was the first new brand since 1886 to use the Coca-Cola trademark. The product quickly overtook the company's existing diet cola, Tab, in sales.
Pepsi
According to Consumer Reports, in the 1970s, the rivalry continued to heat up the market. Pepsi conducted blind taste tests in stores, in what was called the "Pepsi Challenge". These tests suggested that more consumers preferred the taste of Pepsi (which is believed to have more lemon oil, and less orange oil, and uses vanillin rather than vanilla) to Coke. The sales of Pepsi started to climb, and Pepsi kicked off the "Challenge" across the nation. This became known as the "Cola Wars".