Coffee is a drink produced from the roasted beans of the coffee tree. It is traditionally served hot, but it can also be eaten chilled. Coffee is a stimulant as it has caffeine — usually 80 to 140 mg for every 207 ml depending on the method of preparation. Coffee is darkly colored, bitter, slightly acidic and has a stimulating effect in humans, primarily due to its caffeine content. It is one of the most popular drinks in the world and can be prepared and presented in a variety of ways (e.g., espresso, French press, caffè latte, or already-brewed canned coffee). It is usually served hot, although chilled or iced coffee is common. Sugar, sugar substitutes, milk or cream are often used to lessen the bitter taste or enhance the flavor. It may be served with coffee cake or another sweet dessert, like doughnuts. Learn more here.