Diet Coke
Diet Coke does not use a modified form of the Coca-Cola recipe, but instead an entirely different formula. The controversial New Coke, introduced in 1985, used a version of the Diet Coke recipe that contained high fructose corn syrup and had a slightly different balance of ingredients. In 2004, Coca-Cola introduced Coca-Cola C2, which it claims tastes much closer to Coca-Cola but contains half the carbohydrates. In 2005, the company introduced Coca-Cola Zero (replaced by "Coca-Cola Zero Sugar" in 2017), a sugar-free variation of regular Coca-Cola.
Caffeine-Free Coca-Cola
Caffeine-Free Coca-Cola was introduced in 1983 as a caffeine-free variant of Coca-Cola. It was introduced to compete against Pepsi Free, which is now called Caffeine-Free Pepsi. The diet variant, Caffeine-Free Diet Coke, was the first variant of Diet Coke and was introduced in 1984, one year before the regular Coke version. In 2013, Caffeine-Free Coca-Cola Zero was introduced in America.