Hot chocolate, also known as hot cocoa, is a heated beverage typically consisting of shaved chocolate, melted chocolate or cocoa powder, heated milk or water, and sugar. Some make a distinction between hot chocolate made with melted chocolate versus powdered, calling the former drinking chocolate. Drinking chocolate is also characterized by less sweetness and thicker consistency. The first chocolate beverage is believed to have been created by the Maya around 2,000 years ago, and a cocoa beverage was an essential part of Aztec culture by 1400 AD. The beverage became popular in Europe after being introduced from Mexico in the New World and has undergone multiple changes since then. Until the 19th century, hot chocolate was even used medicinally to treat ailments such as liver and stomach diseases. Today, hot chocolate is consumed throughout the world and comes in multiple variations including the very thick cioccolata densa served in Italy, and the thinner hot cocoa that is typically consumed in the United States.